$ git clone -n https://src.fedoraproject.org/rpms/golang-cloud-google-bigquery.git /var/lib/mock/f40-build-2238212-53561/root/chroot_tmpdir/scmroot/golang-cloud-google-bigquery
Cloning into '/var/lib/mock/f40-build-2238212-53561/root/chroot_tmpdir/scmroot/golang-cloud-google-bigquery'...
$ git fetch origin 8a1924962003e78d941eb2ab8582237f1995227e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-cloud-google-bigquery
 * [new ref]         8a1924962003e78d941eb2ab8582237f1995227e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8a19249 Disable bootstrap mode