$ git clone -n https://src.fedoraproject.org/rpms/mongo-c-driver.git /var/lib/mock/f41-build-side-1-3071781-38818/root/chroot_tmpdir/scmroot/mongo-c-driver
Cloning into '/var/lib/mock/f41-build-side-1-3071781-38818/root/chroot_tmpdir/scmroot/mongo-c-driver'...
$ git fetch origin 7d3a54733f3032f4b7cb5e1779b82d415db4d71a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mongo-c-driver
 * [new ref]         7d3a54733f3032f4b7cb5e1779b82d415db4d71a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7d3a547 update to 1.29.0