Add regression test for false positive invalid-name on attrs class var

[zenlyj]

Type of Changes

	Type
✓	🐛 Bug fix
	✨ New feature
	🔨 Refactoring
	📜 Docs

Description

Issue should be fixed with pylint-dev/astroid#2811. Mainly adding a regression test here.

Closes #10525

[zenlyj]

Let me know if I need include a changelog here, there is already one on astroid side so I am unsure if we need one here as well

[Pierre-Sassoulas]

LGTM ! pylint is the "front", I think there's a lot less person reading astroid's release note, so it's good to have a changelog in pylint for astroid changes with pylint consequences.

[DanielNoord]

We don't have attrs as a test dependency.

Considering we already have a regression test in astroid, should we just leave this out of pylint and consider the issue fixed?

[Pierre-Sassoulas]

Fair enough, I would be okay with adding attr as a dev dependencie too, there's always issue with it it seems.

[zenlyj]

Let's go with leaving this test out, probably cleaner that way as well, rather than adding a file dedicated to a single issue. I'll go ahead and close this PR and put the issue as completed.