Fix prepare_single_hop_path_and_storage_options

Fix `_prepare_single_hop_path_and_storage_options`:
- Do not pass HF authentication headers and HF user-agent to non-HF HTTP URLs
- Do not overwrite passed `storage_options` nested values:
  - Before, when passed 
    ```DownloadConfig(storage_options={"https": {"client_kwargs": {"raise_for_status": True}}})```, 
    it was overwritten to 
    ```{"https": {"client_kwargs": {"trust_env": True}}}```
  - Now, the result combines both: 
    ```{"https": {"client_kwargs": {"trust_env": True, "raise_for_status": True}}}```

Comments:
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_7068). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

<details>
<summary>Show benchmarks</summary>

PyArrow==8.0.0

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005725 / 0.011353 (-0.005628) | 0.004149 / 0.011008 (-0.006859) | 0.065051 / 0.038508 (0.026543) | 0.030220 / 0.023109 (0.007111) | 0.256768 / 0.275898 (-0.019130) | 0.269767 / 0.323480 (-0.053713) | 0.003256 / 0.007986 (-0.004730) | 0.003378 / 0.004328 (-0.000951) | 0.049407 / 0.004250 (0.045156) | 0.046041 / 0.037052 (0.008988) | 0.270977 / 0.258489 (0.012488) | 0.288771 / 0.293841 (-0.005070) | 0.030401 / 0.128546 (-0.098145) | 0.012203 / 0.075646 (-0.063443) | 0.227365 / 0.419271 (-0.191906) | 0.036356 / 0.043533 (-0.007176) | 0.262763 / 0.255139 (0.007624) | 0.268172 / 0.283200 (-0.015028) | 0.020698 / 0.141683 (-0.120984) | 1.171679 / 1.452155 (-0.280476) | 1.155353 / 1.492716 (-0.337363) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.138740 / 0.018006 (0.120733) | 0.300962 / 0.000490 (0.300473) | 0.000240 / 0.000200 (0.000040) | 0.000050 / 0.000054 (-0.000005) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.019056 / 0.037411 (-0.018355) | 0.062922 / 0.014526 (0.048396) | 0.075339 / 0.176557 (-0.101218) | 0.122587 / 0.737135 (-0.614548) | 0.078622 / 0.296338 (-0.217716) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.273878 / 0.215209 (0.058669) | 2.753188 / 2.077655 (0.675533) | 1.446877 / 1.504120 (-0.057243) | 1.325034 / 1.541195 (-0.216160) | 1.332849 / 1.468490 (-0.135641) | 0.721042 / 4.584777 (-3.863735) | 2.457241 / 3.745712 (-1.288471) | 3.008013 / 5.269862 (-2.261848) | 1.925773 / 4.565676 (-2.639903) | 0.077725 / 0.424275 (-0.346550) | 0.005232 / 0.007607 (-0.002375) | 0.331398 / 0.226044 (0.105354) | 3.273689 / 2.268929 (1.004761) | 1.818291 / 55.444624 (-53.626334) | 1.532233 / 6.876477 (-5.344244) | 1.545236 / 2.142072 (-0.596837) | 0.809853 / 4.805227 (-3.995374) | 0.137571 / 6.500664 (-6.363093) | 0.042829 / 0.075469 (-0.032640) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.962599 / 1.841788 (-0.879189) | 11.593394 / 8.074308 (3.519086) | 9.564848 / 10.191392 (-0.626544) | 0.131547 / 0.680424 (-0.548876) | 0.014724 / 0.534201 (-0.519477) | 0.309343 / 0.579283 (-0.269940) | 0.263476 / 0.434364 (-0.170888) | 0.350755 / 0.540337 (-0.189582) | 0.445279 / 1.386936 (-0.941657) |

</details>
PyArrow==latest

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005818 / 0.011353 (-0.005534) | 0.004028 / 0.011008 (-0.006980) | 0.050337 / 0.038508 (0.011829) | 0.033234 / 0.023109 (0.010125) | 0.273498 / 0.275898 (-0.002400) | 0.299130 / 0.323480 (-0.024350) | 0.004391 / 0.007986 (-0.003595) | 0.002854 / 0.004328 (-0.001474) | 0.048616 / 0.004250 (0.044365) | 0.040354 / 0.037052 (0.003302) | 0.287980 / 0.258489 (0.029491) | 0.323940 / 0.293841 (0.030099) | 0.033031 / 0.128546 (-0.095515) | 0.012539 / 0.075646 (-0.063108) | 0.061129 / 0.419271 (-0.358143) | 0.034410 / 0.043533 (-0.009123) | 0.276367 / 0.255139 (0.021228) | 0.295266 / 0.283200 (0.012066) | 0.018558 / 0.141683 (-0.123125) | 1.149051 / 1.452155 (-0.303104) | 1.207995 / 1.492716 (-0.284721) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.095732 / 0.018006 (0.077726) | 0.305774 / 0.000490 (0.305284) | 0.000222 / 0.000200 (0.000022) | 0.000044 / 0.000054 (-0.000010) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.023680 / 0.037411 (-0.013731) | 0.077147 / 0.014526 (0.062621) | 0.088850 / 0.176557 (-0.087706) | 0.130219 / 0.737135 (-0.606917) | 0.090582 / 0.296338 (-0.205756) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.306099 / 0.215209 (0.090890) | 2.952515 / 2.077655 (0.874861) | 1.593090 / 1.504120 (0.088970) | 1.471887 / 1.541195 (-0.069308) | 1.484277 / 1.468490 (0.015787) | 0.741158 / 4.584777 (-3.843619) | 0.976520 / 3.745712 (-2.769192) | 2.904631 / 5.269862 (-2.365231) | 1.940287 / 4.565676 (-2.625389) | 0.079828 / 0.424275 (-0.344447) | 0.005482 / 0.007607 (-0.002125) | 0.353376 / 0.226044 (0.127332) | 3.502412 / 2.268929 (1.233483) | 1.976571 / 55.444624 (-53.468053) | 1.675141 / 6.876477 (-5.201336) | 1.821075 / 2.142072 (-0.320998) | 0.814290 / 4.805227 (-3.990937) | 0.135227 / 6.500664 (-6.365437) | 0.041631 / 0.075469 (-0.033838) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 1.041495 / 1.841788 (-0.800293) | 12.275647 / 8.074308 (4.201339) | 10.569540 / 10.191392 (0.378148) | 0.143136 / 0.680424 (-0.537288) | 0.015010 / 0.534201 (-0.519191) | 0.302177 / 0.579283 (-0.277106) | 0.125924 / 0.434364 (-0.308440) | 0.340977 / 0.540337 (-0.199360) | 0.438467 / 1.386936 (-0.948469) |

</details>
</details>

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