$ git clone -n https://src.fedoraproject.org/rpms/libpq.git /var/lib/mock/f41-build-826945-154956/root/chroot_tmpdir/scmroot/libpq
Cloning into '/var/lib/mock/f41-build-826945-154956/root/chroot_tmpdir/scmroot/libpq'...
$ git fetch origin 266c646e51ecfaec22469a2850fb9a5f36d0f944:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libpq
 * [new ref]         266c646e51ecfaec22469a2850fb9a5f36d0f944 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 266c646 Disable ENGINE API