test: nullifier queue failing tests full queue

[ananas-block]

Changes:

• add failing test for nullifier queue operations to show that we cannot insert into a full queue.
  Scenario:

1. try to insert into queue to generate the full error
2. nullify one
3. try to insert again it should still generate the full error
4. advance Merkle tree seq until one before it would work check that it still fails
5. advance Merkle tree seq by one and check that inserting works now
   6.try inserting again it should fail with full error