ci: use yarn for tests

Author: RomainLanz

.github/workflows/checks.yml

@@ -47,11 +47,19 @@ jobs:
         with:
           node-version: 24
 
+      - run: corepack enable
+
+      - name: Setup Node.js cache
+        uses: actions/setup-node@v4
+        with:
+          node-version: 24
+          cache: "yarn"
+
       - name: Install dependencies
-        run: npm install
+        run: yarn
 
       - name: Run tests
-        run: npm test
+        run: yarn test
         env:
           REDIS_HOST: localhost
           REDIS_PORT: 6379