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

Author: renovate[bot]

.github/workflows/main.yml

@@ -14,7 +14,7 @@ jobs:
     container:
       image: ghcr.io/serenity-js/playwright:v1.57.0-noble
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6
       - uses: actions/setup-node@v6
         with:
           node-version: '24.11.1'