[DOC]: Performance documentation landing page is empty

[RAMitchell]

How would you describe the priority of this documentation request

Low

Please provide a link or source to the relevant docs

https://github.com/rapidsai/cugraph/blob/main/readme_pages/performance/performance.md

Describe the problems in the documentation

This page, from the performance link on the front readme, has promised performance results since 2 years ago.

(Optional) Propose a correction

Remove the page and link if no results are available.

Code of Conduct

• I agree to follow cuGraph's Code of Conduct
• I have searched the open documentation issues and have found no duplicates for this bug report

[BradReesWork]

@RAMitchell we used to have some numbers there but are revamping that page. @acostadon and @nv-rliu are working it, but can always use some help