Update actions/checkout action to v6 (#261)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/ci-build.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: git clone
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Set up JDK
         uses: actions/setup-java@v5
         with:

.github/workflows/dependency-submission.yml

@@ -9,7 +9,7 @@ jobs:
   dependency-submission:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: gradle/actions/dependency-submission@v5
         with:
           build-scan-publish: true

.github/workflows/release.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: git clone
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Set up JDK
         uses: actions/setup-java@v5
         with: