Switch to latest caching action

Author: bkimminich

.github/workflows/ci.yml

@@ -40,7 +40,7 @@ jobs:
           node-version: 20
           cache: npm
       - name: "Cache Node.js modules"
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ~/.npm
           key: ${{ runner.OS }}-node-${{ hashFiles('**/package.json') }}