Bump actions/checkout from 6 to 7

Bumps [actions/checkout](https://github.com/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](https://github.com/actions/checkout/compare/v6...v7)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/build.yml

@@ -23,7 +23,7 @@ jobs:
     outputs:
       code: ${{ steps.filter.outputs.code == 'true' || github.event_name == 'release' }}
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: dorny/paths-filter@v4
         id: filter
         if: github.event_name != 'release'
@@ -78,7 +78,7 @@ jobs:
           haskell: true
           large-packages: true
       - uses: hmarr/debug-action@v3
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - name: ccache
         if: matrix.os != 'ubuntu-24.04-arm'
         uses: hendrikmuhs/ccache-action@v1.2
@@ -139,7 +139,7 @@ jobs:
     if: needs.changes.outputs.code == 'true'
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@v7
 
     - name: Build SDist
       run: pipx run build --sdist

.github/workflows/cache-maintenance.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out code
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
 
       - name: Cleanup
         run: |