Fix OutOfMemory Exception

Author: sokoloff06

lib/api_service.dart

@@ -47,10 +47,10 @@ class ApiService {
     return geojsonFile;
   }
 
-  Future<String> getGeoJson() async {
+  Future<String> getGeoJsonUri() async {
     await _initializeAndCacheSpots();
     final geojsonFile = await getGeoJsonFile();
-    return await geojsonFile.readAsString();
+    return geojsonFile.uri.toString();
   }
 
   Future<void> clearLocalData() async {

lib/parking_map_screen.dart

@@ -177,7 +177,7 @@ class _ParkingMapScreenState extends State<ParkingMapScreen> {
       _isLoading = true;
     });
 
-    var data = await _apiService.getGeoJson();
+    var data = await _apiService.getGeoJsonUri();
     await _mapboxMap!.style.addSource(
       mapbox.GeoJsonSource(id: "spots", data: data, cluster: true),
     );