Merge pull request #3890 from rust-lang/renovate/actions-checkout-6.x

Update actions/checkout action to v6

Author: ehuss

.github/workflows/deploy.yml

@@ -12,7 +12,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+    - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       with:
         fetch-depth: 0
     - name: Install mdbook