fix: accept 'required' fields [#285] (#290)

* feat: improve test framework [#281] (#287)

* feat: improve test framework [#281]

* fix: make name change test more sensible [#281]

* fix: obfuscate identifiers better and more often [#281]
# Conflicts:
#	packages/clerk_auth/test/integration/clerk_api/environment_test.dart
#	packages/clerk_auth/test/integration/clerk_api/sign_in_test.dart
#	packages/clerk_auth/test/integration/clerk_api/sign_up_test.dart
#	packages/clerk_auth/test/integration/clerk_api/user_details_test.dart
#	packages/clerk_auth/test/integration/clerk_auth/sign_in_test.dart
#	packages/clerk_auth/test/integration/clerk_auth/sign_up_test.dart
#	packages/clerk_auth/test/test_helpers.dart

* Fix required fields currently not updating when call updateUser (#285)

* Fix required field does not update when call updateUser

Required fields currently not updating when call updateUser in clerk_auth

* Create json_serialization_helpers_test.dart

* fix: change variable name [#285]

* fix: rebase [#285]

* fix: reformat [#285]

---------

Co-authored-by: Krisada Adoolrattananuwat (Tak) <80890688+krisadamqdc@users.noreply.github.com>

Author: shinyford

packages/clerk_auth/lib/src/utils/json_serialization_helpers.dart

@@ -11,8 +11,9 @@ DateTime intToDateTime(dynamic input) {
 /// Convert a [DateTime] to an [int]. For JsonSerializable
 int dateTimeToInt(DateTime dt) => dt.millisecondsSinceEpoch;
 
-/// [true] if a value is ['on'], else [false]. For JsonSerializable
-bool isOn(dynamic on) => on == 'on';
+/// [true] if a value is ['on'] or ['required'], else [false]. For
+/// JsonSerializable
+bool isOn(dynamic value) => value == 'on' || value == 'required';
 
 /// [true] if a value is [true], else [false]. For JsonSerializable
 bool isTrue(dynamic boolean) => boolean == true;