chore(deps): update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/ci.yml

@@ -40,7 +40,7 @@ jobs:
       fail-fast: false
     steps:
       - name: Check out code
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Install Chef
         uses: actionshub/chef-install@3.0.1
       - name: Dokken