Revert "[youtube] Don't use the DASH manifest from 'get_video_info' if 'use_cipher_signature' is True (#5118)"

This reverts commit 87dc451108b278eb5e5600a0159bdbd337272392.

youtube_dl/extractor/youtube.py

@@ -1481,8 +1481,7 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
                     if not video_info_webpage:
                         continue
                     get_video_info = compat_parse_qs(video_info_webpage)
-                    if get_video_info.get('use_cipher_signature') != ['True']:
-                        add_dash_mpd(get_video_info)
+                    add_dash_mpd(get_video_info)
                     if not video_info:
                         video_info = get_video_info
                     if 'token' in get_video_info: