Revert "Bump codecov/codecov-action from 3 to 4 (#279)" (#287)

This reverts commit 6de34a2.

Author: maismail

.github/workflows/unit-test.yml

@@ -67,4 +67,4 @@ jobs:
       run: make test
 
     - name: Publish test coverage
-      uses: codecov/codecov-action@v4
+      uses: codecov/codecov-action@v3