Updated npm in auto build to v12

Added vscode tasks for launching frontend and backend in dev mode

.github/workflows/build.yml

@@ -15,7 +15,10 @@ jobs:
       - name: checkout code
         uses: actions/checkout@v2
       - name: setup node
-        uses: actions/setup-node@v1
+        uses: actions/setup-node@v2
+        with:
+          node-version: '12'
+          cache: 'npm'
       - name: install dependencies
         run: |
           npm install