Update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/integration-test.yml

@@ -19,7 +19,7 @@ jobs:
       json: ${{ steps.generate.outputs.split-index-json }}
     steps:
       - name: Checkout split-tests-java-action
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6
         with:
           repository: donnerbart/split-tests-java-action
 
@@ -48,12 +48,12 @@ jobs:
       JAR_PATH: split-tests-java/build/libs/split-tests-java.jar
     steps:
       - name: Checkout split-tests-java
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6
         with:
           path: split-tests-java
 
       - name: Checkout split-tests-java-action
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6
         with:
           repository: donnerbart/split-tests-java-action
           path: split-tests-java-action

.github/workflows/release.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6
 
       - name: Set up Java
         uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165 # v5

.github/workflows/unit-test.yml

@@ -14,7 +14,7 @@ jobs:
     timeout-minutes: 5
     steps:
       - name: Checkout Split Tests Java
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6
 
       - name: Set up JDK 21
         uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165 # v5