efl_ui_focus_manager: move API into beta which is for debugging
there is no sense to have this outside beta, noone should really use
this. It is only meant for debugging purposes.
Depends on D8271
Reviewers: segfaultxavi, cedric, zmike
Reviewed By: segfaultxavi
Maniphest Tasks: T7726
Differential Revision: https://phab.enlightenment.org/D8272