Timeout when collecting merge requests from GitLab

[fniessink]

Traceback (most recent call last):
  File "/home/collector/base_collectors/source_collector.py", line 109, in __safely_get_source_responses
    responses = await self._get_source_responses(api_url)
  File "/home/collector/source_collectors/gitlab/base.py", line 31, in _get_source_responses
    all_responses.extend(responses := await super()._get_source_responses(*next_urls))
  File "/home/collector/base_collectors/source_collector.py", line 137, in _get_source_responses
    raise response
  File "/usr/local/lib/python3.9/site-packages/aiohttp/client.py", line 1104, in throw
    self._coro.throw(arg)
  File "/usr/local/lib/python3.9/site-packages/aiohttp/client.py", line 544, in _request
    await resp.start(conn)
  File "/usr/local/lib/python3.9/site-packages/aiohttp/client_reqrep.py", line 905, in start
    self._continue = None
  File "/usr/local/lib/python3.9/site-packages/aiohttp/helpers.py", line 656, in __exit__
    raise asyncio.TimeoutError from None
asyncio.exceptions.TimeoutError

This aiohttp issue seems to be the cause: aio-libs/aiohttp#2217.