.github: Bump actions/add-to-project from 0.5.0 to 0.6.0

Bumps [actions/add-to-project](https://github.com/actions/add-to-project) from 0.5.0 to 0.6.0.
- [Release notes](https://github.com/actions/add-to-project/releases)
- [Commits](actions/add-to-project@31b3f3c...0609a27)

---
updated-dependencies:
- dependency-name: actions/add-to-project
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/pr-triage.yml

@@ -15,7 +15,7 @@ jobs:
           repo-token: "${{ secrets.GITHUB_TOKEN }}"
       - name: Assign to Dashboard project
         # https://github.com/marketplace/actions/add-to-github-projects?version=v0.5.0
-        uses: actions/add-to-project@31b3f3ccdc584546fc445612dec3f38ff5edb41c
+        uses: actions/add-to-project@0609a2702eefb44781da00f8e04901d6e5cd2b92
         with:
           project-url: https://github.com/orgs/ceph/projects/2
           github-token: ${{ secrets.ADD_TO_PROJECT_PAT }}