Smart grouping for commits from renovate (e.g. branch automerge mode)

[pat-s]

Currently, skipCommitsWithoutPullRequest: true is the default and hence skips all commits which haven't been merged through a PR.
This will skip all commits when using the branchautomerge setting in renovate.
While one can skipCommitsWithoutPullRequest: false, all of these commits won't have a label and will be automatically put into the "Misc" category.

After #182, I'd suggest to

• group all renovate updates by default into the "Dependency" category
• find a way correctly group renovate commits through branch automerge (should be doable through the commit title pattern)
• Add an option to not ignore branch-automerge commits by default, e.g. something like AlwaysIncludeRenovateCommits: true. This would still skip "normal" commits but by default include branch-automerge renovate commits

(All of the above might not only apply to renovate but also to other dep automation tools like GHs dependency bot).

[pat-s]

Example for branch-automerge commits (with skipCommitsWithoutPullRequest: false).

If renovate uses conventional commits, one could look for the chore(deps): pattern and automatically assign such commits to the "dependency" section.

Yet, first a logic to process based on commit messages would need to be added.

Another improvement that comes to my mind: Only keep the most recent commit for dependencies. I.e., it is not helpful to anyone to include every bump of a particular dependency, only the most recent one matters for the release notes. Could be done by some smart regex matching that

1. only processes entries that start with chore(deps):
2. Requires a minimum of characters to exactly match, e.g. "30". This should prevent false-positives to be processed/removed