Release note tools: Don't cache commits with unknown modules

The script for collecting bug fixes per release have a caching feature
to speed up frequent re-running of the script by triagers to sort
commits.

This commit changes the script so that fix commits that don't have a
known module are no longer cached.

This is done because part of the sorting of commits is making sure
they're assigned to the right module. This typically means checking
on commits with "Unknown" modules and giving them a module label.

However due to caching, triagers running the script won't see those
changes until they clear their cache. To fix this, we no longer cache
commits with unknown modules.

Pull Request: https://projects.blender.org/blender/blender/pulls/138503

release/release_notes/bug_fixes_per_major_release.py

@@ -893,7 +893,8 @@ def cached_commits_store(list_of_commits: list[CommitInfo]) -> None:
     # on commits that are already sorted (and they're not interested in).
     data_to_cache = {}
     for commit in list_of_commits:
-        if (commit.classification not in (NEEDS_MANUAL_SORTING, IGNORED)) and not (commit.has_been_overwritten):
+        if (commit.classification not in (NEEDS_MANUAL_SORTING, IGNORED)) and not (
+                commit.has_been_overwritten) and (commit.module != UNKNOWN):
             commit_hash, data = commit.prepare_for_cache()
             data_to_cache[commit_hash] = data