update codecov-action (#78930)

Updates the codecov-action from beta to latest version 4.6.0.

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.github/workflows/codecov_per_test_coverage.yml

@@ -61,7 +61,7 @@ jobs:
       # it reduces large coverage fluctuations
       - name: Upload coverage - special case to test Codecov ATS
         if: ${{ always() }}
-        uses: codecov/codecov-action@428cda1b1c731be3e8bfa389049c3f276d572ffb # v4-beta
+        uses: codecov/codecov-action@015f24e6818733317a2da2edd6290ab26238649a # v5.0.7
         env:
           CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
         with: