build: update CI to node 14 LTS (#29)

Author: keithamus

.github/workflows/nodejs.yml

@@ -27,10 +27,10 @@ jobs:
           key: ${{ runner.os }}-node-modules-${{ hashFiles('**/package-lock.json') }}
           restore-keys: |
             ${{ runner.os }}-node-modules-
-      - name: Use Node.js 12
+      - name: Use Node.js 14
         uses: actions/setup-node@v2
         with:
-          node-version: '12'
+          node-version: '14'
 
       - name: Install dependencies
         run: npm install