Updated workflow file

Author: sunil-lakshman

.github/workflows/unit-test.yml

@@ -33,7 +33,7 @@ jobs:
           coverage-badge -o coverage.svg
 
       - name: Upload coverage artifact
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: coverage-report
           path: |