$ git clone -n https://src.fedoraproject.org/rpms/rust-gtk4-sys0.6.git /var/lib/mock/f38-build-side-43-rust-devel-1421746-31465/root/chroot_tmpdir/scmroot/rust-gtk4-sys0.6
Cloning into '/var/lib/mock/f38-build-side-43-rust-devel-1421746-31465/root/chroot_tmpdir/scmroot/rust-gtk4-sys0.6'...
$ git fetch origin ac7b743891421f2d66cdc9ddc1812ccb3c5646d9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gtk4-sys0.6
 * [new ref]         ac7b743891421f2d66cdc9ddc1812ccb3c5646d9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ac7b743 Drop non-installable v4_12 feature