Bump actions/checkout from 5 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/automerge.yml

@@ -9,7 +9,7 @@ jobs:
                 browser: ["chrome", "opera", "firefox"]
         runs-on: ubuntu-latest
         steps:
-            - uses: actions/checkout@v5
+            - uses: actions/checkout@v6
             - uses: actions/setup-node@v6
               with:
                   node-version: "20.x"

.github/workflows/codeql-analysis.yml

@@ -20,7 +20,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
 
     - name: Initialize CodeQL
       uses: github/codeql-action/init@v4