docs: Update refs to Efl.Ui.Theme.Apply_Error

Summary:
Proper refs to particular errors cannot be added until T7736 is resolved.

Ref T7717

Test Plan: Only docs updated

Reviewers: zmike

Reviewed By: zmike

Subscribers: cedric, reviewers, committers

Tags: efl

Maniphest Tasks: T7717

Differential Revision: https://phab.enlightenment.org/D8495