Bump actions/checkout from 4 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...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/CI.yml

@@ -16,7 +16,7 @@ jobs:
         browser: [chrome]  # firefox, chrome, headlesschrome, edge
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - name: Set up Python ${{ matrix.python-version }} with Robot Framework ${{ matrix.rf-version }}
       uses: actions/setup-python@v5
       with:

.github/workflows/Select.yml

@@ -26,7 +26,7 @@ jobs:
             browser: chrome
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - name: Configuration Description
       run: |
         echo "${{ matrix.config.description }} configuration"