$ git clone -n https://src.fedoraproject.org/rpms/rust-base64_0.12.git /var/lib/mock/f40-build-2710780-71762/root/chroot_tmpdir/scmroot/rust-base64_0.12
Cloning into '/var/lib/mock/f40-build-2710780-71762/root/chroot_tmpdir/scmroot/rust-base64_0.12'...
$ git fetch origin 007ff4109219b4deaa411fa2585300db49ed89a6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-base64_0.12
 * [new ref]         007ff4109219b4deaa411fa2585300db49ed89a6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 007ff41 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild