fix: remove unused imports

Author: AiroPi

src/connect4/core.py

@@ -2,7 +2,7 @@
 
 from dataclasses import dataclass
 from enum import Enum
-from typing import Any, Literal, Sequence, TypeAlias, cast
+from typing import Sequence, TypeAlias
 
 from connect4.errors import ColumnFull, GameOver, InvalidColumn
 

tests/test_connect4.py

@@ -1,6 +1,3 @@
-from pprint import pprint
-from sqlite3 import connect
-
 import connect4
 import pytest