$ git clone -n https://src.fedoraproject.org/rpms/ghc-aeson-compat.git /var/lib/mock/f39-build-2201848-51855/root/chroot_tmpdir/scmroot/ghc-aeson-compat
Cloning into '/var/lib/mock/f39-build-2201848-51855/root/chroot_tmpdir/scmroot/ghc-aeson-compat'...
$ git fetch origin d0c0cc7c19954d87c2905148d4e2f374b348cfd1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-aeson-compat
 * [new ref]         d0c0cc7c19954d87c2905148d4e2f374b348cfd1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d0c0cc7 fix AesonException ambiguity with aeson-2.1