$ git clone -n https://src.fedoraproject.org/rpms/rubygem-bacon.git /var/lib/mock/f45-build-34794-691/root/chroot_tmpdir/scmroot/rubygem-bacon
Cloning into '/var/lib/mock/f45-build-34794-691/root/chroot_tmpdir/scmroot/rubygem-bacon'...
$ git fetch origin 3c5a7320051f9ba33af20306f89801fe7ee24d1d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-bacon
 * [new ref]         3c5a7320051f9ba33af20306f89801fe7ee24d1d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3c5a732 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild