Repository: youtube-dl
Issue: cannot correctly resolve `bilibili.com` video URLs contained in a festival / bilibili.com 的包含在 festival 中的视频链接不能被正确解析
Labels: broken-IE

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## Checklist

<!--
Carefully read and work through this check list in order to prevent the most common mistakes and misuse of youtube-dl:
- First of, make sure you are using the latest version of youtube-dl. Run `youtube-dl --version` and ensure your version is 2021.12.17. If it's not, see https://yt-dl.org/update on how to update. Issues with outdated version will be REJECTED.
- Make sure that all provided video/audio/playlist URLs (if any) are alive and playable in a browser.
- Make sure that all URLs and arguments with special characters are properly quoted or escaped as explained in http://yt-dl.org/escape.
- Search the bugtracker for similar issues: http://yt-dl.org/search-issues. DO NOT post duplicates.
- Finally, put x into all relevant boxes (like this [x])
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- [x] I'm reporting a broken site support
- [x] I've verified that I'm running youtube-dl version **2021.12.17**
- [x] I've checked that all provided URLs are alive and playable in a browser
- [x] I've checked that all URLs and arguments with special characters are properly quoted or escaped
- [x] I've searched the bugtracker for similar issues including closed ones


## Verbose log

<!--
Provide the complete verbose output of youtube-dl that clearly demonstrates the problem.
Add the `-v` flag to your command line you run youtube-dl with (`youtube-dl -v <your command line>`), copy the WHOLE output and insert it below. It should look similar to this:
 [debug] System config: []
 [debug] User config: []
 [debug] Command-line args: [u'-v', u'http://www.youtube.com/watch?v=BaW_jenozKcj']
 [debug] Encodings: locale cp1251, fs mbcs, out cp866, pref cp1251
 [debug] youtube-dl version 2021.12.17
 [debug] Python version 2.7.11 - Windows-2003Server-5.2.3790-SP2
 [debug] exe versions: ffmpeg N-75573-g1d0487f, ffprobe N-75573-g1d0487f, rtmpdump 2.4
 [debug] Proxy map: {}
 <more lines>
-->

```
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: ['https://www.bilibili.com/video/BV1dZ4y1Y7bt', '-v']
[debug] Encodings: locale cp936, fs mbcs, out cp936, pref cp936
[debug] youtube-dl version 2021.12.17
[debug] Python version 3.4.4 (CPython) - Windows-10-10.0.19041
[debug] exe versions: none
[debug] Proxy map: {}
[BiliBili] 1dZ4y1Y7bt: Downloading webpage
[BiliBili] 1dZ4y1Y7bt: Downloading video info page
ERROR: Unable to extract title; please report this issue on https://yt-dl.org/bug . Make sure you are using
 the latest version; type  youtube-dl -U  to update. Be sure to call youtube-dl with the --verbose flag and
 include its complete output.
Traceback (most recent call last):
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmpupik7c6w\build\youtube_dl\Youtube
DL.py", line 815, in wrapper
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmpupik7c6w\build\youtube_dl\Youtube
DL.py", line 836, in __extract_info
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmpupik7c6w\build\youtube_dl\extract
or\common.py", line 534, in extract
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmpupik7c6w\build\youtube_dl\extract
or\bilibili.py", line 213, in _real_extract
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmpupik7c6w\build\youtube_dl\extract
or\common.py", line 1021, in _html_search_regex
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmpupik7c6w\build\youtube_dl\extract
or\common.py", line 1012, in _search_regex
youtube_dl.utils.RegexNotFoundError: Unable to extract title; please report this issue on https://yt-dl.org
/bug . Make sure you are using the latest version; type  youtube-dl -U  to update. Be sure to call youtube-
dl with the --verbose flag and include its complete output.
```


## Description

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cannot correctly resolve `bilibili.com` video URLs which is contained in a festival. for example,

```
https://www.bilibili.com/festival/lty10th?bvid=BV1dZ4y1Y7bt
```

while a normal video(not contained in a festival) URL should look like

```
https://www.bilibili.com/video/BVxxxxxxxx
```

but using `https://www.bilibili.com/video/BV1dZ4y1Y7bt` still does not work for it auto redirects back to the festival URL.

bilibili.com 的包含在 festival 中的视频链接不能被正确解析。