Use conventional commits

[helpermethod]

When reading release notes, it's hard to spot bug fixes amongst new features, dependency updates etc..

While JReleaser allows you to categorize changelog entries, Quarkus' commits are just not uniform enough to categorize them. Thus I suggest to use Conventional Commits to allow automatic categorization by JReleaser.

/CC @aalmiray

[aalmiray]

FWIW I think Quarkus does not use JReleaser for generating its changelog (yet 😉 ). However, following a commit message convention (which ever it may be) it's still a Good Idea. If CC is chosen then there are GitHub apps that can enforce abiding to the rules when PRs are checked.