$ git clone -n https://src.fedoraproject.org/rpms/rust-nu-std.git /var/lib/mock/f38-build-side-42-init-devel-1160829-30562/root/chroot_tmpdir/scmroot/rust-nu-std
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1160829-30562/root/chroot_tmpdir/scmroot/rust-nu-std'...
$ git fetch origin 45dd6ce0d467a9beac99481b8d5437fe3150023d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-nu-std
 * [new ref]         45dd6ce0d467a9beac99481b8d5437fe3150023d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 45dd6ce Initial Fedora package