chore: bump actions/checkout from 4.2.1 to 6.0.1

Bumps [actions/checkout](https://github.com/actions/checkout) from 4.2.1 to 6.0.1.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4.2.1...v6.0.1)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: 6.0.1
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/build-and-test.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-20.04
     steps:
       - name: Checkout this repository
-        uses: actions/checkout@v4.2.1
+        uses: actions/checkout@v6.0.1
 
       - name: Build project
         uses: threeal/[email protected]

.github/workflows/deploy-documentation.yml

@@ -17,7 +17,7 @@ jobs:
       cancel-in-progress: true
     steps:
       - name: Checkout this repository
-        uses: actions/checkout@v4.2.1
+        uses: actions/checkout@v6.0.1
 
       - name: Install documentation dependencies
         run: |