Fix AttributeError: 'NoneType' object has no attribute 'get_default_c…

…onverter'

pyathena/connection.py

@@ -234,7 +234,7 @@ def __init__(
         self._converter = converter
         self._formatter = formatter if formatter else DefaultParameterFormatter()
         self._retry_config = retry_config if retry_config else RetryConfig()
-        self.cursor_class = cast(Type[ConnectionCursor], cursor_class)
+        self.cursor_class = cursor_class if cursor_class else cast(Type[ConnectionCursor], Cursor)
         self.cursor_kwargs = cursor_kwargs if cursor_kwargs else {}
         self.kill_on_interrupt = kill_on_interrupt
         self.result_reuse_enable = result_reuse_enable