Teacher can't add tags to lessons and categories to courses

[renatho]

Steps to Reproduce

1. Create a course with a lesson.
2. In the course editor, add a category in the sidebar "Course Categories".
3. In the lesson editor, add a tag in the sidebar "Lesson Tags".
4. Save both.
5. Refresh the page.

What I Expected

Have the lesson tag saved.

What Happened Instead

The tag is not added to the lesson.

PHP / WordPress / Sensei LMS version

PHP 7.4
WP 6.5
Sensei LMS 4.24.0

Browser / OS version

Chrome

Context / Source

Noticed while working on #7613