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/ci.yml

@@ -11,7 +11,7 @@ jobs:
     timeout-minutes: 5
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Check license
         run: DOCKER_BUILDKIT=1 make check-license
       - name: Check deepcopy
@@ -30,7 +30,7 @@ jobs:
     timeout-minutes: 10
     steps:
     - name: Checkout code
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
     - name: Install Go
       uses: actions/setup-go@v6
       with:

.github/workflows/release.yml

@@ -15,7 +15,7 @@ jobs:
     steps:
       -
         name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       -
         name: Setup Go
         uses: actions/setup-go@v6
@@ -44,7 +44,7 @@ jobs:
     steps:
       -
         name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       -
         name: Download artifacts
         uses: actions/download-artifact@v6