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/htaccess.yml

@@ -8,13 +8,13 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - run: ./test/build/test_userbuild.sh
 
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: Build .htaccess
         run: ./bin/build.sh test/conf/.htaccess test/build/htaccess_fixture.conf

.github/workflows/release.yml

@@ -11,7 +11,7 @@ jobs:
   npm:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - run: ./bin/build.sh dist/.htaccess bin/htaccess.conf
       - name: Deploy to NPM
         uses: JS-DevTools/npm-publish@v4.1.1
@@ -21,7 +21,7 @@ jobs:
   github:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - run: ./bin/build.sh dist/h5bp.htaccess bin/htaccess.conf
       - name: Upload Release Asset
         uses: actions/upload-release-asset@v1.0.2

.github/workflows/server.yml

@@ -9,7 +9,7 @@ jobs:
 #  check:
 #    runs-on: ubuntu-latest
 #    steps:
-#      - uses: actions/checkout@v5
+#      - uses: actions/checkout@v6
 #
 #      - name: Check configuration
 #        uses: docker://httpd:latest
@@ -20,7 +20,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: Prepare configs
         run: |