text: Title: Replace Twitter links with Mastodon links
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  ### Details
  
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  Wagtail has decided to move away from Twitter/X to Mastodon (specifically Fostodon):
  
  - https://x.com/WagtailCMS/status/1834237886285103507
  - https://fosstodon.org/@wagtail
  
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  ### Working on this
  
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  For the files we need to change, refer to past PRs that changed `twitter.com` to `x.com`, e.g.
  
  - #12205
  - #12234
  
  There may be some others I have missed.
  
  Anyone can contribute to this. View our [contributing guidelines](https://docs.wagtail.org/en/latest/contributing/index.html), add a comment to the issue once you’re ready to start.
  