evas_textblock: remove special treat for variation sequence text run

Summary:
Now there are no need for special care for variation sequence text run break.
General method will care about all types of characters\

this is also related to D11096

Reviewers: woohyun, bowonryu

Subscribers: cedric, reviewers, committers

Tags: efl

Differential Revision: https://phab.enlightenment.org/D11602