Bump actions/checkout from 4 to 5

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 5.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...v5)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -18,7 +18,7 @@ jobs:
     outputs:
       noxenvs: ${{ steps.noxenvs-matrix.outputs.noxenvs }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Set up nox
         uses: wntrblm/nox@2025.02.09
       - id: noxenvs-matrix
@@ -38,7 +38,7 @@ jobs:
         noxenv: ${{ fromJson(needs.list.outputs.noxenvs) }}
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Install dependencies
         run: sudo apt-get update && sudo apt-get install -y libenchant-2-dev
         if: runner.os == 'Linux' && startsWith(matrix.noxenv, 'docs')
@@ -77,7 +77,7 @@ jobs:
       id-token: write
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Set up Python
         uses: actions/setup-python@v5
         with: