Bump actions/setup-node from 5 to 6 (#84)

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/plan-release.yml

@@ -53,7 +53,7 @@ jobs:
           fetch-depth: 0
           ref: 'master'
       - uses: pnpm/action-setup@v4
-      - uses: actions/setup-node@v5
+      - uses: actions/setup-node@v6
         with:
           node-version: 18
           cache: pnpm

.github/workflows/publish.yml

@@ -47,7 +47,7 @@ jobs:
     steps:
       - uses: actions/checkout@v5
       - uses: pnpm/action-setup@v4
-      - uses: actions/setup-node@v5
+      - uses: actions/setup-node@v6
         with:
           node-version: 18
           # This creates an .npmrc that reads the NODE_AUTH_TOKEN environment variable