Use action instead of bash uploader

.github/workflows/go.yml

@@ -69,6 +69,7 @@ jobs:
         uses: actions/checkout@v2
       - name: measure coverage
         run: make cover
-      - name: report coverage
+      - uses: codecov/codecov-action@v2
-        run: |
+        with:
-          bash <(curl -s https://codecov.io/bash)
+          fail_ci_if_error: true
+          verbose: true