Make tests fail on warnings; add some warnings to ignore list

[artem-shelkovnikov]

This PR makes 2 things:

1. Makes our regular tests fail if a warning happens
2. Ignores several warnings that are not relevant to us (see comments in the ini file)

[jedrazb]

👋 I digged a bit regarding the inheritance warning

• ignore:Inheritance class RetryableAiohttpSession from ClientSession is discouraged:DeprecationWarning
  I don't see a straightforward way to fix it - the root of the warning is that the aiogoogle extends from aiohttp.ClientSession class. The inheritance looks as follows: RetryableAiohttpSession -> aiogoogle.AiohttpSession -> aiohttp.ClientSession and the warning is triggered by transitive closure of our class to aiohttp.ClientSession.

From aiohttp standpoint they prefer aggregation over inheritance, see:

• Discourage inheritance from some aiohttp classes aio-libs/aiohttp#2691
• Warnings for a simple pytest aio-libs/aiohttp#3695 (comment)

That means that in order to get rid of this warning we would need to re-implement aiogoogle.AiohttpSession object with aggregation rather than inheritance from aiohttp.ClientSession - that implies copy-pasting lots of code which can become tech debt immediately when aiogoogle version gets bumped and some potentially breaking changes are introduced.

So my standpoint: let's just silence the warning 🧯

[github-actions]

💔 Failed to create backport PR(s)

The backport operation could not be completed due to the following error:
There are no branches to backport to. Aborting.

The backport PRs will be merged automatically after passing CI.

To backport manually run:
backport --pr 1193 --autoMerge --autoMergeMethod squash