docs: rtl date time format blog (#7936)

* initialize rtl blog post

* edits

* more edits, new video

* edits

* update media

* clarify keyboard navigation

* remove unused imports

* some review fixes

* add more info about bidirectional text

* more follow-ups

* reword

* reword more stuff

* fix videos

* review feedback

* small edits

* grammar

Author: yihuiliao