⬆️ Bump actions/checkout from 5 to 6 in the github-actions group

Bumps the github-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: github-actions
...

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

Author: dependabot[bot]

.github/workflows/docs.yml

@@ -14,7 +14,7 @@ jobs:
     name: Build docs and check links
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - uses: pandoc/actions/setup@v1
     - uses: ts-graphviz/setup-graphviz@v2
     - uses: actions/setup-python@v6

.github/workflows/pre-commit.yml

@@ -18,7 +18,7 @@ jobs:
       github.event.pull_request.head.repo.full_name != github.repository
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - uses: actions/setup-python@v6
     - uses: actions/cache@v4
       with: