update to use more null safe packages (#62525)

Updates all the dependencies used in the most basic test and flutter_test isolates.

dev/tools/gen_keycodes/pubspec.yaml

@@ -8,9 +8,9 @@ environment:
 dependencies:
   args: 1.6.0
   http: 0.12.2
+  meta: 1.3.0-nullsafety.2
   path: 1.8.0-nullsafety
   platform: 2.2.1
-  meta: 1.3.0-nullsafety.2
 
   charcode: 1.2.0-nullsafety # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   collection: 1.15.0-nullsafety.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"

packages/_flutter_web_build_script/pubspec.yaml

@@ -16,7 +16,7 @@ dependencies:
 
   build_runner: 1.10.2
   build_test: 1.2.0
-  build_runner_core: 6.0.0
+  build_runner_core: 5.2.0
   dart_style: 1.3.6
   code_builder: 3.4.0
   build: 1.3.0
@@ -94,4 +94,4 @@ dartdoc:
   # Exclude this package from the hosted API docs.
   nodoc: true
 
-# PUBSPEC CHECKSUM: 715b
+# PUBSPEC CHECKSUM: a25c

packages/flutter_tools/lib/src/commands/update_packages.dart

@@ -57,6 +57,8 @@ const Map<String, String> _kManuallyPinnedDependencies = <String, String>{
   'test_core': '0.3.12-nullsafety.1',
   'typed_data': '1.3.0-nullsafety.2',
   'vector_math': '2.1.0-nullsafety.2',
+  // https://github.com/dart-lang/build/issues/2772
+  'build_runner_core': '5.2.0',
 };
 
 class UpdatePackagesCommand extends FlutterCommand {