feat(build) update build toolchain to Node 14 / npm 7

.github/workflows/ci.yml

     - uses: actions/checkout@v2
     - uses: actions/setup-node@v1
       with:
-        node-version: '12.x'
+        node-version: '14.x'
+    - run: npm i -g npm@7
     - run: npm install
     - run: npm run lint
     - run: npm run test