Bump actions/checkout from 5 to 6 (#272)

Bumps [actions/checkout](https://github.com/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
...

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/dependabot_auto_merge.yml

@@ -20,7 +20,7 @@ jobs:
           github-token: "${{ secrets.GITHUB_TOKEN }}"
           alert-lookup: true
           compat-lookup: true
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Approve a PR if not already approved
 
         run: |

.github/workflows/dependency_review.yml

@@ -12,6 +12,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: 'Checkout Repository'
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: 'Dependency Review'
         uses: actions/dependency-review-action@v4

.github/workflows/mkdocs.yml

@@ -14,7 +14,7 @@ jobs:
 
     steps:
       - name: Checkout main
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0    # Fetch all history for .GitInfo and .Lastmod
       - name: Set up Python 3.10

.github/workflows/mypy.yml

@@ -11,7 +11,7 @@ jobs:
   mypy:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0    # Fetch all history for .GitInfo and .Lastmod
       - name: Set up Python 3.10

.github/workflows/pylint.yml

@@ -11,7 +11,7 @@ jobs:
   linting:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0    # Fetch all history for .GitInfo and .Lastmod
       - name: Set up Python 3.10

.github/workflows/pytest.yml

@@ -11,7 +11,7 @@ jobs:
   pytest:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0    # Fetch all history for .GitInfo and .Lastmod
       - name: Set up Python 3.10

.github/workflows/shellcheck.yml

@@ -10,7 +10,7 @@ jobs:
   shellcheck:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Run ShellCheck
         uses: ludeeus/action-shellcheck@master
         env: