fix analyzer warnings (prefer_single_quotes)

Author: PaulAllanSturm

lib/src/sample_info_list.dart

@@ -14,36 +14,36 @@
 // limitations under the License.
 //
 
-import "sample_info.dart";
-import "samples/add_feature_collection_layer_from_table_sample.dart";
-import "samples/add_feature_layers_sample.dart";
-import "samples/add_tiled_layer_as_basemap_sample.dart";
-import "samples/add_tiled_layer_sample.dart";
-import "samples/add_vector_tiled_layer_sample.dart";
-import "samples/apply_scheduled_updates_to_preplanned_map_area_sample.dart";
-import "samples/apply_simple_renderer_to_feature_layer_sample.dart";
-import "samples/apply_unique_value_renderer_sample.dart";
-import "samples/change_sublayer_renderer_sample.dart";
-import "samples/display_map_sample.dart";
-import "samples/display_points_using_clustering_feature_reduction_sample.dart";
-import "samples/filter_by_definition_expression_or_display_filter_sample.dart";
-import "samples/find_address_sample.dart";
-import "samples/find_closest_facility_sample.dart";
-import "samples/generate_route_with_directions_sample.dart";
-import "samples/identify_layers_sample.dart";
-import "samples/open_mobile_map_sample.dart";
-import "samples/preplanned_offline_map_sample.dart";
-import "samples/query_feature_table_sample.dart";
-import "samples/query_table_statistics_sample.dart";
-import "samples/select_features_in_feature_layer_sample.dart";
-import "samples/serialize_feature_collection_sample.dart";
-import "samples/service_area_sample.dart";
-import "samples/set_basemap_sample.dart";
-import "samples/show_location_sample.dart";
-import "samples/show_magnifier_sample.dart";
-import "samples/simple_marker_symbol_sample.dart";
-import "samples/simulate_location_sample.dart";
-import "samples/suggest_address_sample.dart";
+import 'sample_info.dart';
+import 'samples/add_feature_collection_layer_from_table_sample.dart';
+import 'samples/add_feature_layers_sample.dart';
+import 'samples/add_tiled_layer_as_basemap_sample.dart';
+import 'samples/add_tiled_layer_sample.dart';
+import 'samples/add_vector_tiled_layer_sample.dart';
+import 'samples/apply_scheduled_updates_to_preplanned_map_area_sample.dart';
+import 'samples/apply_simple_renderer_to_feature_layer_sample.dart';
+import 'samples/apply_unique_value_renderer_sample.dart';
+import 'samples/change_sublayer_renderer_sample.dart';
+import 'samples/display_map_sample.dart';
+import 'samples/display_points_using_clustering_feature_reduction_sample.dart';
+import 'samples/filter_by_definition_expression_or_display_filter_sample.dart';
+import 'samples/find_address_sample.dart';
+import 'samples/find_closest_facility_sample.dart';
+import 'samples/generate_route_with_directions_sample.dart';
+import 'samples/identify_layers_sample.dart';
+import 'samples/open_mobile_map_sample.dart';
+import 'samples/preplanned_offline_map_sample.dart';
+import 'samples/query_feature_table_sample.dart';
+import 'samples/query_table_statistics_sample.dart';
+import 'samples/select_features_in_feature_layer_sample.dart';
+import 'samples/serialize_feature_collection_sample.dart';
+import 'samples/service_area_sample.dart';
+import 'samples/set_basemap_sample.dart';
+import 'samples/show_location_sample.dart';
+import 'samples/show_magnifier_sample.dart';
+import 'samples/simple_marker_symbol_sample.dart';
+import 'samples/simulate_location_sample.dart';
+import 'samples/suggest_address_sample.dart';
 
 final List<SampleInfo> sampleInfoList = [
   SampleInfo(

lib/src/samples/change_sublayer_renderer_sample.dart

@@ -50,7 +50,7 @@ class ChangeSublayerRendererSampleState
     final map = ArcGISMap.withBasemapStyle(BasemapStyle.arcGISStreets);
 
     final imageLayer = ArcGISMapImageLayer.withUri(Uri.parse(
-        "https://sampleserver6.arcgisonline.com/arcgis/rest/services/Census/MapServer"));
+        'https://sampleserver6.arcgisonline.com/arcgis/rest/services/Census/MapServer'));
     await imageLayer.load();
     final subLayers = imageLayer.arcGISMapImageSublayers;
     final countiesSublayer = subLayers.elementAt(2);

lib/src/samples/set_basemap_sample.dart

@@ -92,7 +92,7 @@ class SetBasemapSampleState extends State<SetBasemapSample> {
                   );
                 default:
                   return const Center(
-                    child: Text("Loading basemaps..."),
+                    child: Text('Loading basemaps...'),
                   );
               }
             },