ClientResponseError does not include URL

[dkliban]

Long story short

The string representation of ClientResponseErrors only includes the response code and message. It would be more useful for users seeing these errors in logs to know which URL produced the response.

Expected behaviour

File "/usr/local/lib/pulp/lib64/python3.6/site-packages/pulpcore/plugin/download/http.py", line 183, in _run
response.raise_for_status()
File "/usr/local/lib/pulp/lib64/python3.6/site-packages/aiohttp/client_reqrep.py", line 944, in raise_for_status
headers=self.headers)
aiohttp.client_exceptions.ClientResponseError: 404, message='Not Found', url='https://badexample.com'

Actual behaviour

File "/usr/local/lib/pulp/lib64/python3.6/site-packages/pulpcore/plugin/download/http.py", line 183, in _run
response.raise_for_status()
File "/usr/local/lib/pulp/lib64/python3.6/site-packages/aiohttp/client_reqrep.py", line 944, in raise_for_status
headers=self.headers)
aiohttp.client_exceptions.ClientResponseError: 404, message='Not Found'

Steps to reproduce

Make an GET request that you know will produce a 404. Don't handle the exception and then look at the stacktrace printed.

[asvetlov]

Fixed by #3960