Bump actions/checkout from 3 to 6 (#7940)

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v3...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>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/assemble_changelog.yml

@@ -12,7 +12,7 @@ jobs:
       PR_NUMBER: ${{ github.event.pull_request.number }}
       GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
         with:
           ref: ${{github.head_ref}}
 

.github/workflows/rename_changelog_file.yml

@@ -13,7 +13,7 @@ jobs:
       PR_NUMBER: ${{ github.event.pull_request.number }}
       GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
         with:
           ref: ${{github.head_ref}}