Update actions/upload-artifact digest to b4b15b8

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/upload-artifact	action	digest	5d5d22a -> b4b15b8

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Configuration

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.50%. Comparing base (fc8954f) to head (efcc7ec).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #543   +/-   ##
=======================================
  Coverage   96.50%   96.50%           
=======================================
  Files           5        5           
  Lines         315      315           
  Branches       53       45    -8     
=======================================
  Hits          304      304           
  Misses          5        5           
  Partials        6        6