Update workflow.

Author: MoMannn

.github/workflows/node.js.yml

@@ -10,13 +10,13 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [10, 12, 14] # https://nodejs.org/en/about/releases/
+        node-version: [10, 12] # https://nodejs.org/en/about/releases/
     steps:
     - uses: actions/checkout@v2
     - name: Use Node.js ${{ matrix.node-version }}
       uses: actions/setup-node@v2
       with:
         node-version: ${{ matrix.node-version }}
     - run: |
-        npm i
+        npm ci
         npm run solhint && npm test