$ git clone -n https://src.fedoraproject.org/rpms/ghc-snap-core.git /var/lib/mock/f39-build-2029073-47402/root/chroot_tmpdir/scmroot/ghc-snap-core
Cloning into '/var/lib/mock/f39-build-2029073-47402/root/chroot_tmpdir/scmroot/ghc-snap-core'...
$ git fetch origin 3488b4e9f8252c087815a394e63139b7c90fa30a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-snap-core
 * [new ref]         3488b4e9f8252c087815a394e63139b7c90fa30a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3488b4e update to 1.0.5.1