ruff

af43bd4b - [red-knot] Gradual forms do not participate in equivalence/subtyping (#14758)

[red-knot] Gradual forms do not participate in equivalence/subtyping (#14758) ## Summary This changeset contains various improvements concerning non-fully-static types and their relationships: - Make sure that non-fully-static types do not participate in equivalence or subtyping. - Clarify what `Type::is_equivalent_to` actually implements. - Introduce `Type::is_fully_static` - New tests making sure that multiple `Any`/`Unknown`s inside unions and intersections are collapsed. closes #14524 ## Test Plan - Added new unit tests for union and intersection builder - Added new unit tests for `Type::is_equivalent_to` - Added new unit tests for `Type::is_subtype_of` - Added new property test making sure that non-fully-static types do not participate in subtyping