fix: install jq and system deps for Flutter CI action

.gitea/workflows/ci.yml

@@ -11,6 +11,9 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
+      - name: Install system dependencies
+        run: apt-get update && apt-get install -y jq unzip xz-utils curl git
+
       - name: Checkout
         uses: actions/checkout@v4
 
@@ -35,6 +38,9 @@ jobs:
     if: github.event_name == 'push' && github.ref == 'refs/heads/main'
 
     steps:
+      - name: Install system dependencies
+        run: apt-get update && apt-get install -y jq unzip xz-utils curl git
+
       - name: Checkout
         uses: actions/checkout@v4