$ git clone -n https://src.fedoraproject.org/rpms/ghc-http2.git /var/lib/mock/f38-build-side-42-init-devel-577217-26014/root/chroot_tmpdir/scmroot/ghc-http2
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-577217-26014/root/chroot_tmpdir/scmroot/ghc-http2'...
$ git fetch origin c9c8d1b06d1474fb6057b22902ff642618938993:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-http2
 * [new ref]         c9c8d1b06d1474fb6057b22902ff642618938993 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c9c8d1b Convert to %autorelease and %autochangelog