$ git clone -n https://src.fedoraproject.org/rpms/ghc-gi-gio.git /var/lib/mock/f38-build-side-42-init-devel-825767-28363/root/chroot_tmpdir/scmroot/ghc-gi-gio
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-825767-28363/root/chroot_tmpdir/scmroot/ghc-gi-gio'...
$ git fetch origin 0549793cc5b4c91f7f0708770252cfb363f87d4d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-gi-gio
 * [new ref]         0549793cc5b4c91f7f0708770252cfb363f87d4d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0549793 rebuild