[typoascender_exceeds_Agrave] should only run on new families

[m4rc1e]

Observed behaviour

The check typoascender_exceeds_Agrave will run on any family. In reality, we only want to run this check on new families since you'll cause regressions trying to fix this for families that have already been released.

[m4rc1e]

Actually, since Guido opened #3170 perhaps this should be a warn? yeah, lemme downgrade this.