We need to boolean constrain `address_bits_va`

If we do not do this an attacker could pass invaid address bits that are not 0 , 1.

I am unsure if this will cause a problem but its good to be sure/

Something like this from zcash from zcash should fix it.

        for (size_t i = 0; i < INCREMENTAL_MERKLE_TREE_DEPTH; i++) {
            // TODO: This might not be necessary, and doesn't
            // appear to be done in libsnark's tests, but there
            // is no documentation, so let's do it anyway to
            // be safe.
            generate_boolean_r1cs_constraint<FieldT>(
                this->pb,
                positions[i],
                "boolean_positions"
            );
}

Cross posting in miximus. But I hope we can finish the miximus rewrite with Semaphore as a dependency so we don't need to make this fix over there.

barryWhiteHat / semaphore

We need to boolean constrain `address_bits_va` #8