Bump actions/checkout from 6.0.3 to 7.0.0 (#530)

Bumps [actions/checkout](https://github.com/actions/checkout) from 6.0.3 to 7.0.0.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@df4cb1c...9c091bb)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: 7.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
     runs-on: ubuntu-24.04
 
     steps:
-      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
 
       - uses: r-lib/actions/setup-r@d3c5be51b12e724e68f33216ca3c148b66d5f0b6
         with:

.github/workflows/lint.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-24.04
 
     steps:
-      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
 
       - uses: r-lib/actions/setup-r@d3c5be51b12e724e68f33216ca3c148b66d5f0b6
         with: