In Bitbucket, you currently have the ability to tracking analytics via the google analytics key in the settings.  However, google is migrating to a slightly different tracking method (requiring a G4 property instead of universal analytics).  See this:

https://support.google.com/analytics/answer/12938611#zippy=%2Cin-this-article

So this results in a different key, and I tried migrating mine and it doesn't work.  So I think the few lines in the html need to be updated according to the new tagging method.

Supposedly by July 2023, this will all stop working for everyone if you don't update it.