$ git clone -n https://src.fedoraproject.org/rpms/rust-gio.git /var/lib/mock/f40-build-2100526-50469/root/chroot_tmpdir/scmroot/rust-gio
Cloning into '/var/lib/mock/f40-build-2100526-50469/root/chroot_tmpdir/scmroot/rust-gio'...
$ git fetch origin 71212b0eb029208b6090f461c5a32e45c0bfb5e2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gio
 * [new ref]         71212b0eb029208b6090f461c5a32e45c0bfb5e2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 71212b0 Update to version 0.18.2; Fixes RHBZ#2239030