fix: search for release commit with commit_subject - #488

@d-ryzhikov this looks like a good catch! Since we don't want to identify the current version with a commit that doesn't match the specified commit_subject, is it worth adding an explicit test that a commit in the log which doesn't match the commit_subject template but contains the current version returns None?

@bernardcooke53 I've added a test for a case when there is a commit with a message containing current version but the subject doesn't match commit_subject setting. However, in this case evaluate_version_bump shouldn't return None. Instead it should not evaluate this commit as the release commit and continue the search.

@d-ryzhikov looks good! Yes you're right about the bump, in my head I was thinking of an out-of-scope commit not triggering a bump - the way you've done it is good too 🙂

I updated the release commit search logic in evaluate_version_bump and in generate_changelog. Now the release commit check is more strict: a commit message for a target version is constructed and only commits with exactly matching messages are considered to be target version commits.