$ git clone -n https://src.fedoraproject.org/rpms/rubygem-timecop.git /var/lib/mock/f45-build-35397-695/root/chroot_tmpdir/scmroot/rubygem-timecop
Cloning into '/var/lib/mock/f45-build-35397-695/root/chroot_tmpdir/scmroot/rubygem-timecop'...
$ git fetch origin de7f6596fbb332207ea0e20f875bb3269cb559e9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-timecop
 * [new ref]         de7f6596fbb332207ea0e20f875bb3269cb559e9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at de7f659 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild