meta: bump actions/setup-node from 3 to 6

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 3 to 6.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](actions/setup-node@v3...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] <support@github.com>

Author: dependabot[bot]

.github/workflows/nodejs-ci-action.yml

@@ -18,7 +18,7 @@ jobs:
     steps:
     - uses: actions/checkout@v3
     - name: Use Node.js ${{ matrix.node-version }}
-      uses: actions/setup-node@v3
+      uses: actions/setup-node@v6
       with:
         node-version: ${{ matrix.node-version }}
     - run: npm ci

.github/workflows/release-please.yml

@@ -16,7 +16,7 @@ jobs:
 
       - uses: actions/checkout@v3
         if: ${{ steps.release.outputs.release_created }}
-      - uses: actions/setup-node@v3
+      - uses: actions/setup-node@v6
         with:
           node-version: 20
           registry-url: 'https://registry.npmjs.org'