Bump actions/checkout from 5 to 6

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>

Author: dependabot[bot]

.github/workflows/lint.yml

@@ -21,7 +21,7 @@ jobs:
     timeout-minutes: 15
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           repository: ${{ github.event.pull_request.head.repo.full_name }}
           ref: ${{ github.event.pull_request.head.ref }}

.github/workflows/pages.yml

@@ -25,7 +25,7 @@ jobs:
     if: github.repository_owner == 'seqan'
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Setup conda
         uses: conda-incubator/setup-miniconda@v3

.github/workflows/test.yml

@@ -23,7 +23,7 @@ jobs:
     steps:
       # pull_request_target does not checkout the merge commit by default
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           ref: "refs/pull/${{ github.event.number }}/merge"