$ git clone -n https://src.fedoraproject.org/rpms/isomaster.git /var/lib/mock/f31-build-54065-27939/root/thebuilddir/tmp/scmroot/isomaster
Cloning into '/var/lib/mock/f31-build-54065-27939/root/thebuilddir/tmp/scmroot/isomaster'...
$ git reset --hard 9ab3994b3c1153d821526747da72940fbfc0076a
HEAD is now at 9ab3994 - Rebuilt for https://fedoraproject.org/wiki/Fedora_30_Mass_Rebuild