Make connect and connect_robust generic

[glav-git]

Fixes #695

Just a draft on how issue could be resolved. Gave a detailed explanation on why this is a good idea in the issue itself. Since it's just a typing change, should't be a breaking change in the api?

[coveralls]

coverage: 91.981% (+0.004%) from 91.977%
when pulling 544fe41 on glav-git:master
into 57029c3 on mosquito:master.

[glav-git]

I noticed my commit introduced 2 new mypy errors:

aio_pika/connection.py:319: error: Incompatible default for argument "connection_class" (default has type "type[Connection]", argument has type "type[CT]")  [assignment]
aio_pika/robust_connection.py:276: error: Incompatible default for argument "connection_class" (default has type "type[RobustConnection]", argument has type "type[CT]")  [assignment]

Unfortunately it's known issue: python/mypy#3737 and so far I was not able to find any solution that would satisfy both mypy and pyright at the same time.

So i guess solution here is either # type: ignore[assignment] or just wait until mypy figures out what to do with default values of genericly typed arguments.

[mosquito]

@glav-git # type: ignore[assignment] looks good solution for this case