Move async from member access to construction (#20035)

diff --git a/packages/flutter_tools/lib/src/ios/mac.dart b/packages/flutter_tools/lib/src/ios/mac.dart
index 2105872..e8890f1 100644
--- a/packages/flutter_tools/lib/src/ios/mac.dart
+++ b/packages/flutter_tools/lib/src/ios/mac.dart
@@ -233,7 +233,7 @@
   final Directory appDirectory = fs.directory(app.appDirectory);
   await _addServicesToBundle(appDirectory);
 
-  final FlutterProject project = new FlutterProject(fs.currentDirectory);
+  final FlutterProject project = await FlutterProject.current();
   await updateGeneratedXcodeProperties(
     project: project,
     targetOverride: targetOverride,