bfix: Provide Firebase config secret during CI.

Author: BURG3R5

.github/workflows/ci.yml

@@ -4,6 +4,7 @@ on: [ push ]
 
 env:
   SENTRY_DSN: ${{ secrets.SENTRY_DSN }}
+  FIREBASE_CONFIG: ${{ secrets.FIREBASE_CONFIG }}
 
 jobs:
   lint:
@@ -70,6 +71,8 @@ jobs:
         run: flutter pub get
       - name: Generate Freezed models
         run: flutter pub run build_runner build --delete-conflicting-outputs
+      - name: Provide Firebase config file
+        run: echo $FIREBASE_CONFIG | base64 --decode > android/app/google-services.json
 
       # Build
       - name: Build APK