$ git clone -n https://src.fedoraproject.org/rpms/perl-String-Compare-ConstantTime.git /var/lib/mock/f45-build-26272-616/root/chroot_tmpdir/scmroot/perl-String-Compare-ConstantTime
Cloning into '/var/lib/mock/f45-build-26272-616/root/chroot_tmpdir/scmroot/perl-String-Compare-ConstantTime'...
$ git fetch origin 1700eae5ef4589a91205c352b9288671fcd66f69:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-String-Compare-ConstantTime
 * [new ref]         1700eae5ef4589a91205c352b9288671fcd66f69 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1700eae Perl 5.44 rebuild