fix: use pnpm in CI

.github/workflows/test_integration.yml

@@ -23,11 +23,18 @@ jobs:
       - name: Setup tmate session
         uses: mxschmitt/action-tmate@v3
         if: ${{ github.event_name == 'workflow_dispatch' && inputs.debug_enabled }}
-
-      - name: Set up Node.js
+
+      - name: Install pnpm
+        uses: pnpm/action-setup@v4
+        with:
+          version: 9
+      - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v4
         with:
-          node-version: 'latest'
+          node-version: ${{ matrix.node-version }}
+          cache: 'pnpm'
+      - name: Install dependencies
+        run: pnpm install
 
       - name: Install dependencies
         run: npm ci