fix: Add missing f-string from app_analytics models

[zachaysan]

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Changes

While looking into our various databases on the backend I noticed these strings were missed and quickly fixed them.

How did you test this code?

The change is simple enough to rely on CI / common sense.

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[codecov-commenter]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (76cc152) 96.10% compared to head (e4373f3) 96.10%.
Report is 5 commits behind head on main.

Files	Patch %	Lines
api/app_analytics/models.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3155   +/-   ##
=======================================
  Coverage   96.10%   96.10%           
=======================================
  Files        1058     1058           
  Lines       31882    31882           
=======================================
  Hits        30641    30641           
  Misses       1241     1241           

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