ci(github): replace Coveralls with Codecov in workflow build.yml

Author: remarkablemark

.github/workflows/build.yml

@@ -49,7 +49,5 @@ jobs:
       - name: Run benchmark
         run: npm run benchmark
 
-      - name: Coveralls
-        uses: coverallsapp/github-action@master
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Codecov
+        uses: codecov/codecov-action@v2