Added api for custom timetable events

lib/api/mhsl/customTimetableEvent/get/getCustomTimetableEventParams.dart

@@ -0,0 +1,13 @@
+import 'package:json_annotation/json_annotation.dart';
+
+part 'getCustomTimetableEventParams.g.dart';
+
+@JsonSerializable()
+class GetCustomTimetableEventParams {
+  String user;
+
+  GetCustomTimetableEventParams(this.user);
+
+  factory GetCustomTimetableEventParams.fromJson(Map<String, dynamic> json) => _$GetCustomTimetableEventParamsFromJson(json);
+  Map<String, dynamic> toJson() => _$GetCustomTimetableEventParamsToJson(this);
+}