(docs): Add corepack instructions to README.md

[tatethurston]

https://stackoverflow.com/questions/70082424/command-not-found-corepack-when-installing-yarn-on-node-v17-0-1

[Stratus3D]

@augustobmoura can you review this PR?

@tatethurston I think generally, you developers should run asdf reshim nodejs after running a command that adds a nodejs executable to the user's path. These instructions might be overly specific.

[mgtitimoli]

Hey there,

I landed here following a comment on an issue, it would be great if we can merge this one 🙂 so people could easily know how to use other package managers.

Thanks!

[Stratus3D]

@augustobmoura any thoughts here?

[Stratus3D]

Merging for now. We can always revert or edit later.