Derive elgamal key in token client (#3308)

* token-2022: derive elgamal key in token client

* token-2022: update program tests for key derivation

* token-2022: key derivation for apply pending balance

* token-2022: add configure account with max pending balance

* token-2022: update tests for apply pending balance

* token-2022: derive key for confidential trasfer with fee

* token-2022: update test for confidential transfer with fee

* token-2022: derive encryption keys for withdrawing withheld tokens

* token-2022: update tests

Author: samkim-crypto