Bump codecov/codecov-action from 3.0.0 to 3.1.0 (#2343)

Author: dependabot[bot]

.github/workflows/tests.yml

@@ -78,7 +78,7 @@ jobs:
 
     - name: Upload coverage to Codecov
       if: ${{ matrix.update-coverage }}
-      uses: codecov/codecov-action@e3c560433a6cc60aec8812599b7844a7b4fa0d71 #v3
+      uses: codecov/codecov-action@81cd2dc8148241f03f5839d295e000b8f761e378 #v3.1.0
 
     - name: Ensure go generate produces a zero diff for update-urls
       shell: bash