Update actions/checkout action to v7

Author: renovate[bot]

.github/workflows/build.yml

@@ -9,7 +9,7 @@ jobs:
     name: Build for Android
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@v7
     - name: Install Ninja
       run: sudo apt-get install -y ninja-build
     - uses: actions/setup-java@v5
@@ -40,7 +40,7 @@ jobs:
     name: Build for iOS
     runs-on: macos-15
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@v7
     - uses: maxim-lobanov/setup-xcode@v1
       with:
         xcode-version: latest-stable
@@ -59,7 +59,7 @@ jobs:
     name: Build for macOS
     runs-on: macos-15
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: maxim-lobanov/setup-xcode@v1
         with:
           xcode-version: latest-stable
@@ -82,7 +82,7 @@ jobs:
     name: Build for Windows
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: subosito/flutter-action@v2
         with:
           channel: 'stable'

.github/workflows/docusaurus.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout source code
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
 
       - name: Setup Node.js
         uses: actions/setup-node@v6

.github/workflows/publish.yml

@@ -8,7 +8,7 @@ jobs:
     name: Build for Android
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@v7
     - name: Install Ninja
       run: sudo apt-get install -y ninja-build
     - uses: actions/setup-java@v5
@@ -131,7 +131,7 @@ jobs:
     name: Build for Windows
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - name: Setup Flutter
         uses: subosito/flutter-action@v2
         with:
@@ -188,7 +188,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: [build-android, build-windows] #[build-android, build-macos, build-windows]
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - name: Download Android artifacts
         uses: actions/download-artifact@v8
         with: