CLI install docs doesn't mention aliasing

[kristian-nst]

There's this page: https://bun.sh/guides/install/npm-alias

It's linking you to the full docs (https://bun.sh/docs/cli/install), but the full docs doesn't have this aliasing section anywhere 😂

[RiskyMH]

Fixed in #15754, let me know if you wanted more (I think it's pretty basic)