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] <[email protected]>

Author: dependabot[bot]

.github/workflows/generate_files.yml

@@ -33,9 +33,9 @@ jobs:
           echo "::set-output name=commitURL::${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}/commit/${GITHUB_SHA}"
           echo "::set-output name=jobURL::${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}/actions/runs/${GITHUB_RUN_ID}"
 
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: Checkout BC Files Generator repo
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           repository: kiegroup/build-chain-files-generator
           path: build-chain-files-generator