From the announcement email in konflux-users: 
 

 
TLDR: If you want automated reviewer selection in build-definitions (like it used to work before), consider configuring the github code review settings for your team. If you don't have a team in github and would like this functionality, consider asking one of the konflux-ci owners to create a team for you.
 
Context:
 
If you're a build-definitions contributor, you may have noticed that we have set up a CODEOWNERS file to manage task ownership. Changes to a task now require a review from an owner as defined in CODEOWNERS. But unlike the past, they only require a review from the owner to be merge-able - you will no longer depend on the build/integration teams to get your changes in.
 
Going forward, we will generally expect teams and individuals that contribute tasks to take ownership of them.
 
A side effect of this change is that we lost the automatic reviewer selection from openshift-ci. If you liked this feature and would like something similar back, see the TLDR at the top of this email.

 
We have https://github.com/orgs/3scale/teams/productization that we can use.