Bitwise AND between BigInt that come from PrimeField

[hdvanegasm]

Hi everyone,

I wan to implement the following function considering the last contribution to bitwise operations between BigInt (#713):

use ark_ff::fields::PrimeField;

fn compute_and<F: PrimeField>(a: F, b: F) -> F {
    let a_bigint = a.into_bigint();
    let b_bigint = b.into_bigint();
    let and_bigint =  a_bigint & b_bigint;
    let and_field = match F::from_bigint(and_bigint) {
        Some(value) => value,
        None => panic!("Something bad happened."),
    };

    and_field
}

This code is incorrect, and the output shows the following error which I can understand:

error[E0308]: mismatched types
  --> src/main.rs:7:42
   |
6  |     let and_bigint =  a_bigint & b_bigint;
   |                       ------------------- here the type of `and_bigint` is inferred to be `<<F as PrimeField>::BigInt as BitAnd>::Output`
7  |     let and_field = match F::from_bigint(and_bigint) {
   |                           -------------- ^^^^^^^^^^ expected `ark_ff::PrimeField::BigInt`, found `std::ops::BitAnd::Output`
   |                           |
   |                           arguments to this function are incorrect
   |
   = note: expected associated type `<F as PrimeField>::BigInt`
              found associated type `<<F as PrimeField>::BigInt as BitAnd>::Output`
   = note: an associated type was expected, but a different one was found
note: associated function defined here
  --> /home/hdvanegasm/.cargo/git/checkouts/algebra-7e23afa68841b66e/b7b988f/ff/src/fields/prime.rs:55:8
   |
55 |     fn from_bigint(repr: Self::BigInt) -> Option<Self>;
   |        ^^^^^^^^^^^

For more information about this error, try `rustc --explain E0308`.
error: could not compile `ark` (bin "ark") due to previous error

Is it possible to implement this function for arbitrary PrimeField elements with the current state of the library, or do we need to extend the functionality by submitting a PR?