chore: update openapi (#8470)

mobile/openapi/test/on_this_day_dto_test.dart

@@ -0,0 +1,27 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+// @dart=2.12
+
+// ignore_for_file: unused_element, unused_import
+// ignore_for_file: always_put_required_named_parameters_first
+// ignore_for_file: constant_identifier_names
+// ignore_for_file: lines_longer_than_80_chars
+
+import 'package:openapi/api.dart';
+import 'package:test/test.dart';
+
+// tests for OnThisDayDto
+void main() {
+  // final instance = OnThisDayDto();
+
+  group('test OnThisDayDto', () {
+    // num year
+    test('to test the property `year`', () async {
+      // TODO
+    });
+
+
+  });
+
+}