$ git clone -n https://src.fedoraproject.org/rpms/perl-Test-Mock-Guard.git /var/lib/mock/f45-build-26737-619/root/chroot_tmpdir/scmroot/perl-Test-Mock-Guard
Cloning into '/var/lib/mock/f45-build-26737-619/root/chroot_tmpdir/scmroot/perl-Test-Mock-Guard'...
$ git fetch origin ad81d49d43251ec1d94049a42685754d5e2daf36:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Test-Mock-Guard
 * [new ref]         ad81d49d43251ec1d94049a42685754d5e2daf36 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ad81d49 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild