[flutter_tools] do not delete web directory during flutter build web (#69115)

packages/flutter_tools/lib/src/web/compile.dart

@@ -36,10 +36,8 @@ Future<void> buildWeb(
   final bool hasWebPlugins = (await findPlugins(flutterProject))
     .any((Plugin p) => p.platforms.containsKey(WebPlugin.kConfigKey));
   final Directory outputDirectory = globals.fs.directory(getWebBuildDirectory());
-  if (outputDirectory.existsSync()) {
-    outputDirectory.deleteSync(recursive: true);
-    outputDirectory.createSync(recursive: true);
-  }
+  outputDirectory.createSync(recursive: true);
+
   await injectPlugins(flutterProject, webPlatform: true);
   final Status status = globals.logger.startProgress('Compiling $target for the Web...');
   final Stopwatch sw = Stopwatch()..start();