Move prosemirror-suggest to a seperate repository

[ifiokjr]

Description

prosemirror-suggest was always meant to be a standalone project.

It should be moved into a new repository which lives under the remirror organisation.

I'm still unsure over whether this should be a single package repo called remirror/prosemirror-suggest or whether I should create a remirror/prosemirror monorepo with scope for adding more prosemirror specific packages.