$ git clone -n https://src.fedoraproject.org/rpms/rubygem-tilt.git /var/lib/mock/f38-build-side-42-init-devel-647864-26439/root/chroot_tmpdir/scmroot/rubygem-tilt
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-647864-26439/root/chroot_tmpdir/scmroot/rubygem-tilt'...
$ git fetch origin 79afa3ed451db331b479d775eea891839d16c197:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-tilt
 * [new ref]         79afa3ed451db331b479d775eea891839d16c197 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 79afa3e Update to Tilt 2.0.11.