It says, for ReadOnly mode(recommended), You need to implement support for ReadOnly-mode for this to work.
A number of customers have reached out to support to ask, "Do I need to apply those manually like in this document https://world.optimizely.com/documentation/developer-guides/CMS/Deployment/database-mode/?".
To provide clarification on the document. You do not need to do anything, the deployment process of Paasportal handles it totally for you.