Bump the actions group across 1 directory with 2 updates

Bumps the actions group with 2 updates in the / directory: [actions/checkout](https://github.com/actions/checkout) and [codecov/codecov-action](https://github.com/codecov/codecov-action).


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)

Updates `codecov/codecov-action` from 5 to 6
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/main/CHANGELOG.md)
- [Commits](codecov/codecov-action@v5...v6)

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

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

Author: dependabot[bot]

.github/workflows/documentation.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     name: deploy to gh-pages
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Set up Python 3.10
         uses: actions/setup-python@v6
         with:

.github/workflows/testing.yml

@@ -17,7 +17,7 @@ jobs:
         python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v6
       with:
@@ -34,7 +34,7 @@ jobs:
       run: |
         pytest --cov=./ --cov-report=xml tests/
     - name: Upload coverage to Codecov
-      uses: codecov/codecov-action@v5
+      uses: codecov/codecov-action@v6
       with:
         fail_ci_if_error: false # optional (default = false)
         token: ${{ secrets.CODECOV_TOKEN }}