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/htcc.yml

@@ -33,7 +33,7 @@ jobs:
           cmd /c "`"${VSRoot}/VC/Auxiliary/Build/vcvarsall.bat`" x64&set" `
             | Where-Object { $_ -like '*=*' } `
             | Out-File -Encoding utf8 -Append $Env:GITHUB_ENV
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           path: source
           fetch-depth: 0

.github/workflows/pages.yml

@@ -24,7 +24,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Setup Ruby
         uses: ruby/setup-ruby@v1
         with: