- Dont shadow widgets destroy()
- Dont bind spell checker to class attribute, this prevents its finalize

Fixes #8822

Gtk Objects like a TreeModel is not detected correctly

- E0611 no-name-in-module
- E1133 not-an-iterable
- E1136 unsubscriptable-object

- E0611 no-name-in-module
- E0710 raising-non-exception
- E0712 catching-non-exception
- E1133 not-an-iterable
- E1136 unsubscriptable-object

- Ignore some pylint errors only in CI, not locally
- Set max line length to 80

Fixes #9633

Fixes #9643

Some attributes of the certificate can yield None

- Simplify modules because nbxmpp handles more stuff