workflow: change flutter version

.github/workflows/build.yml

@@ -13,7 +13,8 @@ jobs:
       - name: Set up Flutter
         uses: subosito/flutter-action@v2
         with:
-          flutter-version: '3.1.3'
+          channel: 'stable'
+          flutter-version: '3.x'
       - run: flutter config --enable-linux-desktop
       - run: flutter pub get
       - name: Build for Linux
@@ -33,7 +34,8 @@ jobs:
       - name: Set up Flutter
         uses: subosito/flutter-action@v2
         with:
-          flutter-version: '3.1.3'
+          channel: 'stable'
+          flutter-version: '3.x'
       - uses: actions/setup-java@v2
         with:
           distribution: 'zulu'
@@ -59,7 +61,8 @@ jobs:
       - name: Set up Flutter
         uses: subosito/flutter-action@v2
         with:
-          flutter-version: '3.1.3'
+          channel: 'stable'
+          flutter-version: '3.x'
       - name: Enable flutter web
         run: flutter config --enable-web
       - name: Get dependencies

.github/workflows/test.yml

@@ -8,15 +8,16 @@ jobs:
     name: Run Tests
     runs-on: ubuntu-latest
     steps:
-    - name: Checkout code
-      uses: actions/checkout@v2
-    - name: Set up Flutter
-      uses: subosito/flutter-action@v2
-      with:
-        flutter-version: '3.1.3'
-    - name: Get dependencies
-      run: flutter pub get
-    - name: Analyze
-      run: flutter analyze
-    - name: Run tests
-      run: flutter test
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Set up Flutter
+        uses: subosito/flutter-action@v2
+        with:
+          channel: 'stable'
+          flutter-version: '3.x'
+      - name: Get dependencies
+        run: flutter pub get
+      - name: Analyze
+        run: flutter analyze
+      - name: Run tests
+        run: flutter test