[dependabot][ghaction] - (deps): Bump the all-actions group across 1 directory with 2 updates

Bumps the all-actions group with 2 updates in the / directory: [actions/checkout](https://github.com/actions/checkout) and [actions/upload-artifact](https://github.com/actions/upload-artifact).


Updates `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)

Updates `actions/upload-artifact` from 4 to 5
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v4...v5)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: all-actions
- dependency-name: actions/upload-artifact
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: all-actions
...

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

Author: dependabot[bot]

.github/workflows/reusable-CI-workflow.yml

@@ -87,7 +87,7 @@ jobs:
             pkg-extra-constraints: --with 'behat/gherkin:~4.12.0' ${{ ( needs.fetch-supported-versions.outputs.symfony-min == '5.4' && needs.fetch-supported-versions.outputs.php-max == '8.4' ) && '--with "symfony/yaml:~6.4.0"' || '' }}
     steps:
       - name: Check out code
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       # Enable coverage only for specific version(s) !
       # Usually highest version(s), plus additional ones in case of code used only with specific versions
@@ -165,7 +165,7 @@ jobs:
 
       - name: Upload coverage reports
         if: ${{ env.COVERAGE_TYPE == 'xdebug' }}
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v5
         with:
           name: coverage-groups-php${{ steps.setup-php.outputs.php-version }}-sf${{ matrix.symfony-version }}
           path: build/coverage-groups
@@ -181,7 +181,7 @@ jobs:
       PHP_VERSION: ${{ needs.fetch-supported-versions.outputs.php-max }}
       SYMFONY_VERSION: ${{ needs.fetch-supported-versions.outputs.symfony-max }}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: Setup PHP ${{ env.PHP_VERSION }}
         id: setup-php
@@ -265,7 +265,7 @@ jobs:
 
     steps:
       - name: Check out code
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Setup PHP ${{ matrix.php-version }}
         id: setup-php