Update readme

Author: object-Object

mindy-website/README.md

@@ -6,7 +6,7 @@ Install `wasm-pack`: https://drager.github.io/wasm-pack/installer/
 
 ```sh
 rustup target add wasm32-unknown-unknown
-wasm-pack build
+wasm-pack build --target web --dev
 
 cd www
 yarn