📙 remove info about mongorocks

[TomWFox]

Link to section:
Please provide a specific link to the section in question. In the docs, you can click on a heading and then copy the relative link from the address bar.

What is the issue?
parse-community/parse-server#6468

Can you propose a solution?
What changes do you think should be made? Have you considered multiple solutions? Will this be suitable for all use cases?