BIPs 327, 340: remove unused imports

Co-authored-by: Snezhkko <snezhkodaria38@gmail.com>

bip-0327/reference.py

@@ -4,7 +4,7 @@
 # be used in production environments. The code is vulnerable to timing attacks,
 # for example.
 
-from typing import Any, List, Optional, Tuple, NewType, NamedTuple
+from typing import List, Optional, Tuple, NewType, NamedTuple
 import hashlib
 import secrets
 import time

bip-0340/reference.py

@@ -1,6 +1,5 @@
 from typing import Tuple, Optional, Any
 import hashlib
-import binascii
 
 # Set DEBUG to True to get a detailed debug output including
 # intermediate values during key generation, signing, and