Bump actions/checkout from 5 to 6 in the dependencies group

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


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)

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

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

Author: dependabot[bot]

.github/workflows/doc.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with: { submodules: recursive }
       - uses: prefix-dev/setup-pixi@v0.9.3
         with: { pixi-version: v0.59.0 }

.github/workflows/lint.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with: { submodules: recursive }
       - uses: prefix-dev/setup-pixi@v0.9.3
         with: { pixi-version: v0.59.0 }

.github/workflows/test.yml

@@ -15,7 +15,7 @@ jobs:
         environment: ["python-310", "python-311", "python-312", "python-313"]
         os: ["ubuntu-latest", "ubuntu-24.04-arm", "macos-latest", "windows-latest"]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with: { submodules: recursive }
       - uses: prefix-dev/setup-pixi@v0.9.3
         with: { pixi-version: v0.59.0 }