Bump actions/checkout from 6 to 7 in the actions group

Bumps the actions group with 1 update: [actions/checkout](https://github.com/actions/checkout).


Updates `actions/checkout` from 6 to 7
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v6...v7)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '7'
  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/tests.yml

@@ -26,7 +26,7 @@ jobs:
           - python-version: "3.15"
             os: macos-26
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v6
         with:
@@ -68,7 +68,7 @@ jobs:
     strategy:
       fail-fast: false
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - name: Install uv
         uses: astral-sh/setup-uv@v7
         with:
@@ -116,7 +116,7 @@ jobs:
       UV_SYSTEM_PYTHON: 1
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v6
         with: