ref(metrics): remove span metrics

[shellmayr]

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

:white_check_mark: All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #76590      +/-   ##
==========================================
+ Coverage   79.96%   80.02%   +0.06%     
==========================================
  Files        7064     6902     -162     
  Lines      316313   313844    -2469     
  Branches    52794    54901    +2107     
==========================================
- Hits       252953   251167    -1786     
+ Misses      62922    61055    -1867     
- Partials      438     1622    +1184     

[github-actions[bot]]

🚨 Warning: This pull request contains Frontend and Backend changes!

It's discouraged to make changes to Sentry's Frontend and Backend in a single pull request. The Frontend and Backend are not atomically deployed. If the changes are interdependent of each other, they must be separated into two pull requests and be made forward or backwards compatible, such that the Backend or Frontend can be safely deployed independently.

Have questions? Please ask in the #discuss-dev-infra channel.

[shellmayr]

Was factored into multiple PRs - therefore closing this one.