$ git clone -n https://src.fedoraproject.org/rpms/flatpak-kcm.git /var/lib/mock/f42-build-3359336-45033/root/chroot_tmpdir/scmroot/flatpak-kcm
Cloning into '/var/lib/mock/f42-build-3359336-45033/root/chroot_tmpdir/scmroot/flatpak-kcm'...
$ git fetch origin ef2945fe63fe51b39e90d829f12b0ba7f9a0f174:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/flatpak-kcm
 * [new ref]         ef2945fe63fe51b39e90d829f12b0ba7f9a0f174 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ef2945f 6.3.2