message: Add missing cs.is_satisfied() to bellman test
diff: @@ -1797,6 +1797,8 @@ mod test {
  AllocatedBit::alloc_conditionally(cs.namespace(|| "alloc_conditionally"), value, &b1)
  .unwrap();
  + assert!(cs.is_satisfied());
  +
  //check with true bit
  let mut cs = TestConstraintSystem::<Bls12>::new();
  let b2 = AllocatedBit::alloc(&mut cs, Some(true)).unwrap();
  