[3.14] gh-134151 Fix `TypeError` in `email.utils.decode_params` when sorting RFC 2231 continuations (GH-134687) (#135247)

gh-134151 Fix `TypeError` in `email.utils.decode_params` when sorting RFC 2231 continuations (GH-134687)

- Fix sorting logic in `email.utils.decode_params` to handle None values.
- Update tests for RFC 2231 continuation sorting.
(cherry picked from commit bcb6b45cb86a2f9f65b6c41f27c36059ba86a50b)

Co-authored-by: Jiucheng(Oliver) <git.jiucheng@gmail.com>