[MU4 Task] Add Bilibili links alongside YouTube ones

[Harmoniker1]

Task description It was brought up in #13436 that Bilibili links are to be opened instead of YouTube ones if the language is set to simplified Chinese, since YouTube can't be accessed in Chinese mainland.

The links are:

• Announcing MuseScore 4 - https://www.bilibili.com/video/BV1fv4y197Vc/
• Important Differences - https://www.bilibili.com/video/BV1d14y1K7zf/
• Installing Muse Sounds - https://www.bilibili.com/video/BV18V4y1P78J/
• Engraving Improvements - https://www.bilibili.com/video/BV1Ye4y1T7t3/
• MuseScore in Minutes:
  • Setting up your Score - https://www.bilibili.com/video/BV1Ae4y1M7gU/?p=1
  • The Basics of Score Writing - https://www.bilibili.com/video/BV1Ae4y1M7gU/?p=2
  • Dynamics, Articulation & Tempo - https://www.bilibili.com/video/BV1Ae4y1M7gU/?p=3
  • Guitar & Percussion - https://www.bilibili.com/video/BV1Ae4y1M7gU/?p=4
  • Layouts & Parts - https://www.bilibili.com/video/BV1Ae4y1M7gU/?p=5
  • Text, Lyrics & Chords - https://www.bilibili.com/video/BV1Ae4y1M7gU/?p=6
  • Repeats & Jumps - https://www.bilibili.com/video/BV1Ae4y1M7gU/?p=7
  • Using MIDI Keyboards - https://www.bilibili.com/video/BV1Ae4y1M7gU/?p=8
  • Saving & Publishing to the Cloud - https://www.bilibili.com/video/BV1Ae4y1M7gU/?p=9

As of now, the last 8 videos have not been uploaded, so the links all point to "MuseScore in Minutes - Setting up your Score", but when they are uploaded, they will be put under these exact links.

Hopefully all instances involving opening YouTube links are supplemented with Bilibili links in the app, from the "Learn" page to other special occasions. Thanks!

[David-C0pperfield]

It will be helpful if our users can see them since we have them translated.

[Eism]

@bkunda I think we should create an account on bilibili and transfer all the videos there or do something to control this list with internal resources