Add redirect for Font Collection JSON schema

I would like to request a new JSONJSON JSON, or JavaScript Object Notation, is a minimal, readable format for structuring data. It is used primarily to transmit data between a server and web application, as an alternative to XML. schema file redirect, in line with theme.json and block.json, as discussed in this post.

As part of the new Font Library, there is a new JSON schema for defining font collections. There is more information in this PR.

The new redirect would be for: =>

This should be similar to how the theme.json and block.json redirects have been set up.

Thank you!