Merge pull request #323 from stan-dev/dependabot/github_actions/actions/upload-artifact-6

Bump actions/upload-artifact from 4 to 6

Author: VisruthSK

.github/workflows/test-coverage.yaml

@@ -56,7 +56,7 @@ jobs:
 
       - name: Upload test results
         if: failure()
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: coverage-test-failures
           path: ${{ runner.temp }}/package