Bump actions/checkout from 5 to 6 in the actions group (#1832)

Bumps the actions group with 1 update: [actions/checkout](https://github.com/actions/checkout).


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)

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

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/auto-merge.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: Enable auto-merge for Pull Request
         run: |

.github/workflows/main.yml

@@ -77,7 +77,7 @@ jobs:
           }
         ]
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Build (${{ matrix.targets.base }}/${{ matrix.targets.cmd[0].dir }})
       env:
         LLVM_VERSION: ${{needs.latest_versions.outputs.llvm_version}}