Indexing bug after dataset.select()
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## Describe the bug
A clear and concise description of what the bug is.
 
Dataset indexing is not working as expected after `dataset.select(range(100))`


## Steps to reproduce the bug
```python
# Sample code to reproduce the bug
import datasets

task_to_keys = {
    "cola": ("sentence", None),
    "mnli": ("premise", "hypothesis"),
    "mrpc": ("sentence1", "sentence2"),
    "qnli": ("question", "sentence"),
    "qqp": ("question1", "question2"),
    "rte": ("sentence1", "sentence2"),
    "sst2": ("sentence", None),
    "stsb": ("sentence1", "sentence2"),
    "wnli": ("sentence1", "sentence2"),
}

task_name = "sst2"
raw_datasets = datasets.load_dataset("glue", task_name)


train_dataset = raw_datasets["train"]

print("before select: ",train_dataset[-2:])
# before select:  {'sentence': ['a patient viewer ', 'this new jangle of noise , mayhem and stupidity must be a serious contender for the title . '], 'label': [1, 0], 'idx': [67347, 67348]}

train_dataset = train_dataset.select(range(100))

print("after select: ",train_dataset[-2:])
# after select:  {'sentence': [], 'label': [], 'idx': []}

```

link to colab: https://colab.research.google.com/drive/1LngeRC9f0jE7eSQ4Kh1cIeb411lRXQD-?usp=sharing

## Expected results
A clear and concise description of the expected results.
showing 98, 99 index data

## Actual results
Specify the actual results or traceback.
empty

## Environment info
<!-- You can run the command `datasets-cli env` and copy-and-paste its output below. -->
- `datasets` version: 1.17.0
- Platform: Linux-5.4.144+-x86_64-with-Ubuntu-18.04-bionic
- Python version: 3.7.12
- PyArrow version: 3.0.0
