Update Node.js version

.github/workflows/check.yml

@@ -5,10 +5,10 @@ jobs:
  runs-on: ubuntu-latest
  steps:
  - uses: actions/checkout@v2
- - name: Use Node.js 14
+ - name: Use Node.js 18
  uses: actions/setup-node@v1
  with:
- node-version: 14
+ node-version: 18
  - name: run markdownlint linter
  run: |
  npm install -g markdownlint-cli