update: Alternate Player Prefabs Connection Approval Process

[NoelStephensUnity]

adding some additional documentation on setting alternate player prefabs within the connection approval process.

Select the type of change:

• Small Changes - Typos, formatting, slight revisions
• New Content - New features, sections, pages, tutorials
• Site and Tools - Updates, maintenance, and new packages for the site and Docusaurus

Purpose of the Pull Request:
This adds additional documentation to help users better understand how they can assign alternate player prefabs via a player prefab's GlobalObjectIdHash value when using the connection approval process.

[armstrongl]

LGTM! Thanks for getting this together so quickly!