Remove mentions of wasm.js from README
Remove mentions of wasm.js from README

It looks like 5580e78e3076b186cfbc64bf64ce8c73ade826b4 removed its need.
WebAssembly/wasm-e2e,binji/wasm-e2e,WebAssembly/wasm-e2e,WebAssembly/wasm-e2e,binji/wasm-e2e,binji/wasm-e2e,WebAssembly/wasm-e2e,binji/wasm-e2e,WebAssembly/wasm-e2e