Clean App.framework, Generated.xcconfig, flutter_export_environment.sh (#51532)

packages/flutter_tools/lib/src/ios/xcodeproj.dart

diff --git a/packages/flutter_tools/lib/src/ios/xcodeproj.dart b/packages/flutter_tools/lib/src/ios/xcodeproj.dart
index d415c39..108436a 100644
--- a/packages/flutter_tools/lib/src/ios/xcodeproj.dart
+++ b/packages/flutter_tools/lib/src/ios/xcodeproj.dart
@@ -357,8 +357,8 @@
     }
   }
 
-  void cleanWorkspace(String workspacePath, String scheme) {
-    _processUtils.runSync(<String>[
+  Future<void> cleanWorkspace(String workspacePath, String scheme) async {
+    await _processUtils.run(<String>[
       _executable,
       '-workspace',
       workspacePath,