$ git clone -n https://src.fedoraproject.org/rpms/perl-Regexp-Grammars.git /var/lib/mock/f41-build-side-1-2807250-32872/root/chroot_tmpdir/scmroot/perl-Regexp-Grammars
Cloning into '/var/lib/mock/f41-build-side-1-2807250-32872/root/chroot_tmpdir/scmroot/perl-Regexp-Grammars'...
$ git fetch origin 0fc89795073f4689c0291818e04e61524a84642d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Regexp-Grammars
 * [new ref]         0fc89795073f4689c0291818e04e61524a84642d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0fc8979 convert GPL+ or Artistic license to SPDX