refactor: set node version via .nvmrc

https://github.com/actions/setup-node/blob/main/docs/advanced-usage.md#node-version-file

Author: mfranzke

.github/workflows/pull-request.yml

@@ -14,10 +14,12 @@ jobs:
         uses: actions/checkout@v3
 
       - name: Set up NodeJS
-        uses: actions/setup-node@v3
+        uses: actions/setup-node@v4
+        with:
+          node-version-file: '.nvmrc'
 
       - name: Install dependencies
-        run: npm install
+        run: npm ci
 
       - name: Run tests
         run: npm test