$ git clone -n https://src.fedoraproject.org/rpms/perl-Crypt-Twofish.git /var/lib/mock/f45-build-22659-593/root/chroot_tmpdir/scmroot/perl-Crypt-Twofish
Cloning into '/var/lib/mock/f45-build-22659-593/root/chroot_tmpdir/scmroot/perl-Crypt-Twofish'...
$ git fetch origin a7f75253cd07374b1f4c0dd2c0be6afcf05c1220:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Crypt-Twofish
 * [new ref]         a7f75253cd07374b1f4c0dd2c0be6afcf05c1220 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a7f7525 Perl 5.44 rebuild