Add missing trailing commas (#28673)

* add trailing commas on list/map/parameters

* add trailing commas on Invocation with nb of arg>1

* add commas for widget containing widgets

* add trailing commas if instantiation contains trailing comma

* revert bad change

dev/bots/test.dart

diff --git a/dev/bots/test.dart b/dev/bots/test.dart
index a7536be..74e32e2 100644
--- a/dev/bots/test.dart
+++ b/dev/bots/test.dart
@@ -309,7 +309,7 @@
 Future<void> _pubRunTest(
   String workingDirectory, {
   String testPath,
-  bool enableFlutterToolAsserts = false
+  bool enableFlutterToolAsserts = false,
 }) {
   final List<String> args = <String>['run', 'test', '-rcompact', '-j1'];
   if (!hasColor)