This update for smtube fixes the following issues:

Update to version 20.6.0:

* New option in preferences to select the site to use as homepage.
* The internal youtube code has been removed and now smtube just
uses youtube-dl to get the video urls.
* New option in the help menu to help install youtube-dl.

- Youtube-dl is not required, so changed Suggest: youtube-dl to
Required: youtube-dl

This update was imported from the openSUSE:Leap:15.2:Update update project.