build(deps): bump actions/checkout from 5 to 6 (#723)

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/labeler.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Run Labeler
         uses: crazy-max/ghaction-github-labeler@v5.3.0

.github/workflows/release.yml

@@ -17,7 +17,7 @@ jobs:
       id-token: write
     if: ${{ github.repository }} == 'stac-utils/stac-api-validator'
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Set up Python 3.x
         uses: actions/setup-python@v6
         with:

.github/workflows/tests.yml

@@ -33,7 +33,7 @@ jobs:
 
     steps:
       - name: Check out the repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up Python ${{ matrix.python }}
         uses: actions/setup-python@v6
@@ -117,7 +117,7 @@ jobs:
       PIP_CONSTRAINTS: ${{ github.workspace }}/.github/workflows/constraints.txt
     steps:
       - name: Check out the repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6