$ git clone -n https://src.fedoraproject.org/rpms/rubygem-rexical.git /var/lib/mock/f45-build-35216-694/root/chroot_tmpdir/scmroot/rubygem-rexical
Cloning into '/var/lib/mock/f45-build-35216-694/root/chroot_tmpdir/scmroot/rubygem-rexical'...
$ git fetch origin 0803ed24da37e73b76644b760ba20ddee225e3a8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-rexical
 * [new ref]         0803ed24da37e73b76644b760ba20ddee225e3a8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0803ed2 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild