Upgrade: 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] <[email protected]>

Author: dependabot[bot]

.github/workflows/check.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Checkout Repository
-        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # 6.0.0
+        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # 6.0.1
         with:
           persist-credentials: false
           fetch-depth: 0

.github/workflows/test.yml

@@ -10,7 +10,7 @@ jobs:
     timeout-minutes: 30
     steps:
       - name: Checkout Repository
-        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # 6.0.0
+        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # 6.0.1
         with:
           persist-credentials: false
       - name: Set up Gradle