Change from using `defaults` to `plutil` for Plist parsing (#38662)

We were using the `defaults` command-line utility to parse
Plist files, but it was never supported by Apple, and it
appears that in an upcoming OS release, it will be less likely
to work:

> WARNING: The defaults command will be changed in an upcoming
> major release to only operate on preferences domains. General
> plist manipulation utilities will be folded into a different
> command-line program.

Fixes https://github.com/flutter/flutter/issues/37701

packages/flutter_tools/lib/src/project.dart

diff --git a/packages/flutter_tools/lib/src/project.dart b/packages/flutter_tools/lib/src/project.dart
index ef83cfe..1e99c89 100644
--- a/packages/flutter_tools/lib/src/project.dart
+++ b/packages/flutter_tools/lib/src/project.dart
@@ -17,8 +17,7 @@
 import 'features.dart';
 import 'flutter_manifest.dart';
 import 'globals.dart';
-import 'ios/ios_workflow.dart';
-import 'ios/plist_utils.dart' as plist;
+import 'ios/plist_parser.dart';
 import 'ios/xcodeproj.dart' as xcode;
 import 'plugins.dart';
 import 'template.dart';
@@ -361,10 +360,15 @@
   /// The product bundle identifier of the host app, or null if not set or if
   /// iOS tooling needed to read it is not installed.
   String get productBundleIdentifier {
-    final String fromPlist = iosWorkflow.getPlistValueFromFile(
-      hostInfoPlist.path,
-      plist.kCFBundleIdentifierKey,
-    );
+    String fromPlist;
+    try {
+      fromPlist = PlistParser.instance.getValueFromFile(
+        hostInfoPlist.path,
+        PlistParser.kCFBundleIdentifierKey,
+      );
+    } on FileNotFoundException {
+      // iOS tooling not found; likely not running OSX; let [fromPlist] be null
+    }
     if (fromPlist != null && !fromPlist.contains('\$')) {
       // Info.plist has no build variables in product bundle ID.
       return fromPlist;