$ git clone -n https://src.fedoraproject.org/rpms/blake3.git /var/lib/mock/f42-build-882039-184132/root/chroot_tmpdir/scmroot/blake3
Cloning into '/var/lib/mock/f42-build-882039-184132/root/chroot_tmpdir/scmroot/blake3'...
$ git fetch origin 40bc581c50cde1fe71e87b5ae3e20de84ce5cdc7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/blake3
 * [new ref]         40bc581c50cde1fe71e87b5ae3e20de84ce5cdc7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 40bc581 Rebuilt for https://fedoraproject.org/wiki/Fedora_42_Mass_Rebuild