Message Testing

If a module changes, we will always do regression on it.

Assuming a module is not changed, but a message of the module is (spelling/grammar fixes), do we need to run regression on the module still?
Does it need to be a full regression, or can we minimize what is tested somehow?

Checkstyle repo already does UT on message, so it should be verified that way if change works. So do we need to do anything more?

This is blocked by https://github.com/checkstyle/regression-tool/issues/6 (currently) and should be done dead last as it is still not clear if we need to do anything for this.