Add description of how to deploy to web with WebGPU on the wasm page.

[Roeliefantje]

I think it would be useful to add a description of the process of deploying to the web while using webGPU instead of webgl on https://bevy-cheatbook.github.io/platforms/wasm.html.
As in disabling the default features to exclude webgl and to ensure the rustflag(--cfg=web_sys_unstable_apis) is set.