chore: enable codecov

Signed-off-by: Bo-Yi Wu <[email protected]>

Author: appleboy

.github/workflows/go.yml

@@ -64,5 +64,5 @@ jobs:
           go test -v -covermode=atomic -coverprofile=coverage.out .
           go test -v -covermode=atomic -coverprofile=coverage.out ./simple/...
 
-      # - name: Upload coverage to Codecov
-      #   uses: codecov/codecov-action@v1
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v1