Add coveralls test coverage reports

Author: DerAndereAndi

.github/workflows/default.yml

@@ -36,3 +36,8 @@ jobs:
 
       - name: Test
         run: go test -race -v -coverprofile=coverage.out  -covermode=atomic ./...
+
+      - name: Send coverage
+        uses: shogo82148/actions-goveralls@v1
+        with:
+          path-to-profile: coverage.out