Updated flutter installation way

.gitea/workflows/pull_request.yaml

@@ -15,11 +15,18 @@ jobs:
           apt-get update
           apt-get install -y jq
 
-      - name: Set Up Flutter
-        uses: subosito/flutter-action@v2
-        with:
-          channel: 'stable'
-          flutter-version: '3.35.6'
+      - name: Install Flutter
+        run: |
+          # Flutter SDK herunterladen und entpacken
+          wget https://storage.googleapis.com/flutter_infra_release/releases/stable/linux/flutter_linux_3.35.6-stable.tar.xz
+          tar xf flutter_linux_3.35.6-stable.tar.xz
+          # Flutter zum PATH hinzufügen
+          echo "$(pwd)/flutter/bin" >> $GITHUB_PATH
+          # Flutter Doctor ausführen (optional)
+          flutter doctor -v
+
+      - name: Get dependencies
+        run: flutter pub get
 
       - name: Check Formatting
         run: flutter analyze
@@ -31,13 +38,19 @@ jobs:
     needs: lint
 
     steps:
-      - uses: actions/checkout@v4
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Install jq
+        run: |
+          apt-get update
+          apt-get install -y jq
 
       - name: Set Up Flutter
         uses: subosito/flutter-action@v2
         with:
-          flutter-version: 'stable'
           channel: 'stable'
+          flutter-version: '3.35.0'
 
       - name: Get dependencies
         run: flutter pub get