$ git clone -n https://src.fedoraproject.org/rpms/os-autoinst.git /var/lib/mock/f39-build-1677316-40958/root/chroot_tmpdir/scmroot/os-autoinst
Cloning into '/var/lib/mock/f39-build-1677316-40958/root/chroot_tmpdir/scmroot/os-autoinst'...
$ git fetch origin 37d1bdbcf3e9211d547374e7dd1000037b5f2110:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/os-autoinst
 * [new ref]         37d1bdbcf3e9211d547374e7dd1000037b5f2110 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 37d1bdb Update to latest git, resync spec