$ git clone -n https://src.fedoraproject.org/rpms/perl-Text-Diff.git /var/lib/mock/f45-build-26918-620/root/chroot_tmpdir/scmroot/perl-Text-Diff
Cloning into '/var/lib/mock/f45-build-26918-620/root/chroot_tmpdir/scmroot/perl-Text-Diff'...
$ git fetch origin 3b0c72fadea3327b91c09046d19bd11449f93bd3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Text-Diff
 * [new ref]         3b0c72fadea3327b91c09046d19bd11449f93bd3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3b0c72f Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild