$ git clone -n https://src.fedoraproject.org/rpms/perl-Taint-Util.git /var/lib/mock/f45-build-26435-617/root/chroot_tmpdir/scmroot/perl-Taint-Util
Cloning into '/var/lib/mock/f45-build-26435-617/root/chroot_tmpdir/scmroot/perl-Taint-Util'...
$ git fetch origin a483170eb3ca25ead598daa0fc4cd38c3660ba21:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Taint-Util
 * [new ref]         a483170eb3ca25ead598daa0fc4cd38c3660ba21 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a483170 Perl 5.44 rebuild