minimal case:
from typing import ClassVar
from typing import Final
class C:
cv_orig: ClassVar[list[int]] = []
cv_str: 'ClassVar[list[int]]' = []
cv_final_orig: Final[list[int]] = []
cv_final_str: 'Final[list[int]]' = []
use_case: 'Final[list[C]]' = []
with ruff 0.5.1 I got the error
RUF012 Mutable class attributes should be annotated with `typing.ClassVar`
for cv_str, cv_final_str and use_case (that was my initial scenario...)