remove defaulting to the English language

Author: meisnate12

tmdbapis/tmdb.py

@@ -58,7 +58,7 @@ class TMDbAPIs:
             v4_account_id (str): TMDb V4 Account ID.
             v4_access_token (str):  TMDb V4 Access Token.
     """
-    def __init__(self, apikey: str, session_id: Optional[str] = None, v4_access_token: Optional[str] = None, language="en", session: Optional[Session] = None):
+    def __init__(self, apikey: str, session_id: Optional[str] = None, v4_access_token: Optional[str] = None, language=None, session: Optional[Session] = None):
         self._language = None
         self._session = Session() if session is None else session
         self._api4 = API4(v4_access_token, session=self._session) if v4_access_token else None