Bump actions/checkout from 5 to 6

.github/workflows/flutter_build_example.yml

@@ -14,7 +14,7 @@ jobs:
     timeout-minutes: 10
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Setup Java
         uses: actions/setup-java@v5
         with:

.github/workflows/flutter_checks.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Install Flutter
         uses: subosito/flutter-action@v2
       - name: Disable analytics
@@ -28,7 +28,7 @@ jobs:
     timeout-minutes: 10
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Install Flutter
         uses: subosito/flutter-action@v2
       - name: Disable analytics
@@ -44,7 +44,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Install Flutter
         uses: subosito/flutter-action@v2
       - name: Disable analytics
@@ -60,7 +60,7 @@ jobs:
     timeout-minutes: 10
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Install Flutter
         uses: subosito/flutter-action@v2
       - name: Disable analytics
@@ -76,7 +76,7 @@ jobs:
     timeout-minutes: 10
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Install Flutter
         uses: subosito/flutter-action@v2
       - name: Disable analytics

.github/workflows/pub_publish.yml

@@ -9,7 +9,7 @@ jobs:
     name: Pub publish
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Publish
         uses: k-paxian/dart-package-publisher@v1.6
         with:

.github/workflows/pub_publish_dry_run.yml

@@ -11,7 +11,7 @@ jobs:
     name: Pub publish dry run
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Publish dry run
         uses: k-paxian/dart-package-publisher@v1.6
         with:

.github/workflows/pub_score.yml

@@ -12,7 +12,7 @@ jobs:
     name: Check pub score
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: axel-op/dart-package-analyzer@v3
         id: workflow
         with: