Update the readme about AnimatedImage and watchOS

Author: dreampiggy

README.md

@@ -107,6 +107,8 @@ var body: some View {
 
 Note: `AnimatedImage` supports both image url or image data for animated image format. Which use the SDWebImage's [Animated ImageView](https://github.com/SDWebImage/SDWebImage/wiki/Advanced-Usage#animated-image-50) for internal implementation.
 
+Note: `AnimatedImage` does not support watchOS currently. Because there are no Public API to implement it via `WKInterfaceObjectRepresentable` or `SwiftUI.Image`. We need Apple to provide a better solution. But if you're really interested in this, checkout [feature_watchOS_animation](https://github.com/SDWebImage/SDWebImageSwiftUI/tree/feature_watchOS_animation) branch, which using some super hack to support animated image on watchOS.
+
 ## Demo
 
 To run the example using SwiftUI, following the steps: