[v1.28.1]Fixed the bug that occurred in v1.28.0

Thank you for using VRoid Studio. VRoid Studio v1.28.1 update concerns the following: ■ Fixes [list] [*] Fixed a bug occurred in v1.28.0 that prevented transition from the hairstyle editor to the material editor [/list] We will keep looking out for your comments and feedback and work towards new updates. Thank you for your continued support.