Resolve versioned tests and update the required dependencies for python <3.11

- The github action that runs pytest in every python version was actually running pyhton 3.13 for all the cases, so it was useless
- The docs uses myst-parser==4.0.1 which is only supported in python >=3.10 and sphinx==8.2.3 which is only supported in python >=3.11, so both dependencies had been attached to needed python version so uv sync doesn't complain anymore
- No need of tool.uv.dependency-groups.docs anymore
- Rest of the changes are related to some imports not available in python 3.9 and 3.10

findmy/util/abc.py

@@ -6,7 +6,9 @@ import asyncio
 import logging
 from abc import ABC, abstractmethod
 from collections.abc import Mapping
-from typing import TYPE_CHECKING, Generic, Self, TypeVar
+from typing import TYPE_CHECKING, Generic, TypeVar
+
+from typing_extensions import Self
 
 if TYPE_CHECKING:
     from pathlib import Path