$ git clone -n https://src.fedoraproject.org/rpms/rust-derivative.git /var/lib/mock/f40-build-737250-13289/root/chroot_tmpdir/scmroot/rust-derivative
Cloning into '/var/lib/mock/f40-build-737250-13289/root/chroot_tmpdir/scmroot/rust-derivative'...
$ git fetch origin 3fd1fa0dc2cf0d6d5d1b6c8c6c84bd39ae462bf6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-derivative
 * [new ref]         3fd1fa0dc2cf0d6d5d1b6c8c6c84bd39ae462bf6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3fd1fa0 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild