$ git clone -n https://src.fedoraproject.org/rpms/rust-uu_dirname.git /var/lib/mock/f40-build-781162-131432/root/chroot_tmpdir/scmroot/rust-uu_dirname
Cloning into '/var/lib/mock/f40-build-781162-131432/root/chroot_tmpdir/scmroot/rust-uu_dirname'...
$ git fetch origin 15b64e1cc3299347f435614f4bb2a7cb01d2b8c8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-uu_dirname
 * [new ref]         15b64e1cc3299347f435614f4bb2a7cb01d2b8c8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 15b64e1 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild