Upd privacy policy with section for additional cookies tracked on Atlas and Pioneer

### Context

Atlas team would like to refer users to .org privacy policy page for info on cookies. Usersnap feedback tool cookies are not mentioned there at present.

### Suggestion

- [ ] Add a point on Usersnap to Third party cookies section

"[Usersnap](https://usersnap.com/) feedback tool to collect feature requests and feedback on [Atlas](https://play.joystream.org/) and [Pioneer](https://dao.joystream.org/) products. This tool collects [some information](https://help.usersnap.com/docs/for-your-privacy-page#information-collected-by-usersnap) and processes it in accordance with GDPR."

- [ ] Update livesession paragraph, mentioning that it is used on [Atlas(https://play.joystream.org/).

"Livesession is implemented on [Atlas(https://play.joystream.org/), video streaming front end product."