use codecov github actions

.github/workflows/tests.yaml

@@ -6,7 +6,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@master
         with:
           fetch-depth: 2
       - uses: actions/setup-go@v2
@@ -15,4 +15,12 @@ jobs:
       - name: Run coverage
         run: go test -race -coverprofile=coverage.out -covermode=atomic
       - name: Upload coverage to Codecov
-        run: bash <(curl -s https://codecov.io/bash)
+        run: bash <(curl -s https://codecov.io/bash)
+      - uses: codecov/codecov-action@v2
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }} # not required for public repos
+          files: ./coverage.out # optional
+          flags: unittests # optional
+          name: codecov-umbrella # optional
+          fail_ci_if_error: true # optional (default = false)
+          verbose: true # optional (default = false)