Federated Policies, unify add functionality

[peteingithub]

Is your feature request related to a problem? Please describe.
Adding rules in different tabs under Featured Policies have different logic: Add button on left side, Add button on right side, plus sign on right side.

Describe the solution you'd like
Either Add button or plus sign in the same location in the frame.

Additional context

[xingzhang-suse]

It is a UX issue.
It will be a lower priority issue, as no blocker on it.
We need to redesign all the reusable components for this case.