chore(llc): improve test coverage for activity

[renefloor]

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• Code changes are tested (add some information if not applicable)

Description of the pull request

This adds unit tests for the activity class and state

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 13.18%. Comparing base (8c659cc) to head (0c05f07).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##            main      #41      +/-   ##
=========================================
+ Coverage   3.31%   13.18%   +9.87%     
=========================================
  Files        117      117              
  Lines       3139     3139              
=========================================
+ Hits         104      414     +310     
+ Misses      3035     2725     -310     

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