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/sampleApp.yml

@@ -19,7 +19,7 @@ jobs:
     name: Build and test
     runs-on: macos-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - name: List available Xcode versions
       run: ls /Applications | grep Xcode
     - name: Set up Xcode version

.github/workflows/updateMarkdown.yml

@@ -7,7 +7,7 @@ jobs:
   update-markdown-snippets:
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: Run MarkdownSnippets
         run: |
           dotnet tool install --global MarkdownSnippets.Tool