Enable commit linter in juggler monorepo

[bajtos]

This story requires the new monorepo to be created first, see #1725.

Start linting git commit messages to ensure we are following conventional commit style. The solution should pretty much copy what we have in loopback-next.

Caveat: because we are importing existing codebase, we need to find a way how to tell the commit linter to skip linting old imported commits that are not following conventional commit style.

Acceptance criteria

• Commits are linted as part of our CI build/pipeline
• A pre-commit hook configured to lint commits locally too

[stale]

This issue has been marked stale because it has not seen activity within six months. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository. This issue will be closed within 30 days of being stale.

[stale]

This issue has been closed due to continued inactivity. Thank you for your understanding. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository.