fix: better error message when calling extract_info on unavailable video

youtube_dlc/extractor/youtube.py

@@ -1937,6 +1937,7 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
             age_gate = False
             # Try looking directly into the video webpage
             ytplayer_config = self._get_ytplayer_config(video_id, video_webpage)
+            if ytplayer_config:
                 args = ytplayer_config.get("args")
                 if args is not None:
                     if args.get('url_encoded_fmt_stream_map') or args.get('hlsvp'):