Allow passing socket_factory in connector_args

[tomasfarias]

Problem

• aiohttp supports a socket_factory parameter to configure socket settings: https://docs.aiohttp.org/en/stable/client_reference.html#aiohttp.TCPConnector.
  • This was added in aiohttp 3.12.
• Trying to pass socket_factory via AioConfig as a key in connector_args fails the validation check in AioConfig._validate_connector_args.
  • Using latest aiobotocore.

This is similar to #1258, which introduced the ttl_dns_cache argument.

Alternatives

One can get around this by subclassing AioConfig to ignore the check for socket_factory, but it would be better if this was just accepted by aiobotocore.

Development

Happy to send a PR if this is considered a valid issue.

Thank you!