Fix rich text causing prefab fileId to keep changing (cocos#8903)

Merge pull request cocos#8899 from holycanvas/v2.4.6-video

export feature of video

Create tag '3d-v3.2.0'

Create tag '3d-v3.1.1'

fix cc.Follow misspelled word (cocos#8720)

* fix cc.Follow misspelled word

* fit : fit with old functions and warning reminders

* Update CCAction.js

* Add a comment on the obsolete interface

Create tag '3d-v3.1.0'

ban audio playing in editor (cocos#8391)

* ban audio playing in editor

* update audio source

ban audio playing in editor (cocos#8391)

* ban audio playing in editor

* update audio source

Create tag '3d-v3.0.0'

support downloaders (cocos#8241)