[Feature Request] Message Non-Stack Mode

### Existing Component
是

### Component Name
Message

### Description
As we know, the `Message` component runs in 'stack mode' by default. When there is a message box showing on the window, and if you are going to create another new message box, the new one will be stacked under the old one, but sometimes, such behavior isn't what I expected. Instead, I hope the component can provide a "non-stack" mode. When a new message arrives and being displayed on the window, and if there has been an old one appearing on the window, it will dismiss itself and be replaced with the new one.