$ git clone -n https://src.fedoraproject.org/rpms/ghc-servant-foreign.git /var/lib/mock/f39-build-1984178-43348/root/chroot_tmpdir/scmroot/ghc-servant-foreign
Cloning into '/var/lib/mock/f39-build-1984178-43348/root/chroot_tmpdir/scmroot/ghc-servant-foreign'...
$ git fetch origin 7e93572b0bc8e5b985873b94697bdfa2005c0247:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-servant-foreign
 * [new ref]         7e93572b0bc8e5b985873b94697bdfa2005c0247 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7e93572 revised .cabal file