Update main.yml

Author: MacHu-GWU

.github/workflows/main.yml

@@ -55,7 +55,7 @@ jobs:
       # create an CODECOV_TOKEN env var in GitHub actions secret
       - name: "Upload coverage to Codecov"
         if: "${{ contains(env.USING_COVERAGE, matrix.python-version) && github.ref == 'refs/heads/master' }}"
-        uses: "codecov/codecov-action@v4" # https://github.com/marketplace/actions/codecov
+        uses: "codecov/codecov-action@v3" # https://github.com/marketplace/actions/codecov
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           slug: MacHu-GWU/pynamodb_mate-project