Remove wit-bindgen requirement from npm package README

Author: kateinoigakukun

packages/npm-packages/ruby-head-wasm-wasi/README.md

@@ -316,8 +316,6 @@ Error class thrown by Ruby execution
 
 ## Building the package from source
 
-For building the package from source, you need to prepare a Ruby build produced by WASI SDK, and you need [`wit-bindgen`](https://github.com/bytecodealliance/wit-bindgen) and [`wasm-opt`](https://github.com/webassembly/binaryen#tools) in your PATH.
-
 The instructions for building a Ruby targeting WebAssembly are available [here](https://github.com/ruby/ruby.wasm#building-from-source).
 
 Then, you can run the following command in your shell: