QualifyingElement doesn't return warning when using :not()

[wouter-muller]

I am a big fan of the QualifyingElement linter, but when i write some CSS like this using the :not() selector:

li:not(.active) {
  ...
}

It doesn't return a warning, even though i am clearly combining a qualifier + CSS class.

Probably overlooked, so just wanted to drop it here. Would be great if this could be fixed.

[abea]

A new config for the linter might be good here. Though it might be technically a QualifyingElement situation, I think pseudo-classes are different enough from regular classes to have them managed separately.

[sds]

Definitely open to a pull request adding support for this. Thanks!