Add content to raise for status method

added self.content to http_error_msg for helping debugging
Sometimes response content has information that helping debugging.

following is the code I tested.

## Test code
### 402
```
import requests

response = requests.get('https://httpbin.org/status/402')
print(f'status_cod: {response.status_code}')
print(f'content: {response.content}')
print(f'reason: {response.reason}')
response.raise_for_status()
```

### 406
```
import requests

response = requests.get('https://httpbin.org/status/406')
print(f'status_cod: {response.status_code}')
print(f'content: {response.content}')
print(f'reason: {response.reason}')
response.raise_for_status()
```

## Before
### 402
```
status_cod: 402
content: b'Fuck you, pay me!'
reason: PAYMENT REQUIRED
Traceback (most recent call last):
  File "/private/tmp/playground.py", line 7, in <module>
    response.raise_for_status()
  File "/opt/homebrew/lib/python3.11/site-packages/requests/models.py", line 1021, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 402 Client Error: PAYMENT REQUIRED for url: https://httpbin.org/status/402
```

### 406
```
status_cod: 406
content: b'{"message": "Client did not request a supported media type.", "accept": ["image/webp", "image/svg+xml", "image/jpeg", "image/png", "image/*"]}'
reason: NOT ACCEPTABLE
Traceback (most recent call last):
  File "/private/tmp/playground.py", line 7, in <module>
    response.raise_for_status()
  File "/opt/homebrew/lib/python3.11/site-packages/requests/models.py", line 1021, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 406 Client Error: NOT ACCEPTABLE for url: https://httpbin.org/status/406
```

## After
### 402
```
status_cod: 402
content: b'Fuck you, pay me!'
reason: PAYMENT REQUIRED
Traceback (most recent call last):
  File "/private/tmp/playground.py", line 7, in <module>
    response.raise_for_status()
  File "/opt/homebrew/lib/python3.11/site-packages/requests/models.py", line 1021, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 402 Client Error: PAYMENT REQUIRED for url: https://httpbin.org/status/402 content: b'Fuck you, pay me!'
```

### 406
```
status_cod: 406
content: b'{"message": "Client did not request a supported media type.", "accept": ["image/webp", "image/svg+xml", "image/jpeg", "image/png", "image/*"]}'
reason: NOT ACCEPTABLE
Traceback (most recent call last):
  File "/private/tmp/playground.py", line 7, in <module>
    response.raise_for_status()
  File "/opt/homebrew/lib/python3.11/site-packages/requests/models.py", line 1021, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 406 Client Error: NOT ACCEPTABLE for url: https://httpbin.org/status/406 content: b'{"message": "Client did not request a supported media type.", "accept": ["image/webp", "image/svg+xml", "image/jpeg", "image/png", "image/*"]}'
```

Duplicate #2650

To add to what was said in that PR, `self.content` is always bytes so you'll end up with a bytes repr, further the data in the response can very easily be sensitive and it can be enormous. There is no way we will include this in the error

@sigmavirus24
Agree with that point. 
Then how about printing truncated content. For example, if content length is larger than 100, just print self.content[:100].(If preprocess is needed, add the preprocessing logic like self.reason.)

Something sensitive can still be in the first 100 bytes so that's still introducing a vulnerability for anyone that logs the exception without proper scrubbing or sends it to a service like sentry, rollbar, etc which all have questionable track records and shouldn't be trusted with sensitive data.

It's too risky.

No.