add excludeTargetBranch input option

[michaelgwelch]

Trying to figure out how to test my changes.

1. How to just test with a live repo
2. How to add unit tests to your project

Regarding #1: It seems that your version runs instead of mine (even though in my test repo I'm specifically pulling in my version). I assume this is because it downloads and uses your docker image (which I assume has your version of this action in it, or it specifically pulls down your version and runs it).

If you can give me a pointer on how to test this (I don't have a lot of experience writing workflows or custom actions).

Fixes #456 (or will after tested, reviewed, and corrected if necessary)

[michaelgwelch]

Based on my discover and later comment https://github.com/wagoid/commitlint-github-action/issues/456#issuecomment-1406816057 , I think this PR should be closed and instead I could submit a PR where we use git show and a list of shas to get the commit messages.