docs: update yarn configuration

[KY64]

This pull request updates the command needs to configure coc-tsserver using yarn 2+

I've tried following the documentation to use coc-tsserver with yarn 3.1.0 by running

yarn dlx @yarnpkg/pnpify --sdk vim

But I've got the following response on the terminal

$ yarn dlx @yarnpkg/pnpify --sdk vim
➤ YN0000: ┌ Resolution step
➤ YN0000: └ Completed in 7s 504ms
➤ YN0000: ┌ Fetch step
➤ YN0013: │ tunnel@npm:0.0.6 can't be found in the cache and will be fetched fr
➤ YN0013: │ typanion@npm:3.3.2 can't be found in the cache and will be fetched 
➤ YN0013: │ which@npm:2.0.2 can't be found in the cache and will be fetched fro
➤ YN0013: │ wrappy@npm:1.0.2 can't be found in the cache and will be fetched fr
➤ YN0013: │ yallist@npm:4.0.0 can't be found in the cache and will be fetched f
➤ YN0000: └ Completed in 2s 411ms
➤ YN0000: ┌ Link step
➤ YN0000: └ Completed in 0s 229ms
➤ YN0000: Done in 10s 201ms

Usage Error: The 'pnpify --sdk ...' command has been moved to the '@yarnpkg/sdks' package - use 'yarn dlx @yarnpkg/sdks ...' instead

It turns out that the command has already moved as docummented here, so @yarnpkg/pnpify no longer include sdk configuration. Hence, to configure coc-tsserver using yarn 2+ we could run

yarn dlx @yarnpkg/sdks vim

EDIT:

You can read the documentation here https://yarnpkg.com/getting-started/editor-sdks