Bump actions/setup-node from 5 to 6 (RustPython#6197)

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 5 to 6.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](actions/setup-node@v5...v6)

---
updated-dependencies:
- dependency-name: actions/setup-node
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/ci.yaml

@@ -389,7 +389,7 @@ jobs:
           python-version: ${{ env.PYTHON_VERSION }}
       - run: python -m pip install -r requirements.txt
         working-directory: ./wasm/tests
-      - uses: actions/setup-node@v5
+      - uses: actions/setup-node@v6
         with:
           cache: "npm"
           cache-dependency-path: "wasm/demo/package-lock.json"

.github/workflows/release.yml

@@ -112,7 +112,7 @@ jobs:
 
       - name: install wasm-pack
         run: curl https://rustwasm.github.io/wasm-pack/installer/init.sh -sSf | sh
-      - uses: actions/setup-node@v5
+      - uses: actions/setup-node@v6
       - uses: mwilliamson/setup-wabt-action@v3
         with: { wabt-version: "1.0.30" }
       - name: build demo