$ git clone -n https://src.fedoraproject.org/rpms/perl-Alien-m4.git /var/lib/mock/f45-build-21639-587/root/chroot_tmpdir/scmroot/perl-Alien-m4
Cloning into '/var/lib/mock/f45-build-21639-587/root/chroot_tmpdir/scmroot/perl-Alien-m4'...
$ git fetch origin 560a36fc1178ec4f18985167c4fddc30a3342f1e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Alien-m4
 * [new ref]         560a36fc1178ec4f18985167c4fddc30a3342f1e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 560a36f Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild