scripts: zephyr_commit_rules: improve commit error messages

Make the error messages which appear in CI for invalid commit messages
match the text in the documentation which describes the rules for
commit messages exactly. This hopefully makes it easier for people to
read failing CI results and map them to documentation links describing
what to do instead.

Signed-off-by: Marti Bolivar <marti.bolivar@nordicsemi.no>
1 file changed