Bump actions/setup-node from 4 to 6

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 4 to 6.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](actions/setup-node@v4...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/test.yml

@@ -7,7 +7,7 @@ jobs:
           - name: checkout repo
             uses: actions/checkout@v5
           - name: use node.js
-            uses: actions/setup-node@v4
+            uses: actions/setup-node@v6
             with:
               node-version: '20.x'
           - run: npm install # TODO change to npm ci when package.json and package-lock.json are in sync