chore(deps): update actions/setup-node action to v6

Author: renovate[bot]

.github/workflows/build-test-ci.yml

@@ -18,7 +18,7 @@ jobs:
         with:
           version: 8
       - name: Setting up Node.js ${{ matrix.node-version }}
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: ${{ matrix.node-version }}
           cache: "pnpm"