$ git clone -n https://src.fedoraproject.org/rpms/ghc-memory.git /var/lib/mock/f41-build-838882-159867/root/chroot_tmpdir/scmroot/ghc-memory
Cloning into '/var/lib/mock/f41-build-838882-159867/root/chroot_tmpdir/scmroot/ghc-memory'...
$ git fetch origin 6a55e61a526328769840a59b099ba0289ab367d0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-memory
 * [new ref]         6a55e61a526328769840a59b099ba0289ab367d0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6a55e61 bump release