Implement opt-in or out app updates

[Artx-II]

Describe your suggested feature

SongTube performs an update check in the background every time the app is opened, but a one-time dialog to let the user choose to opt-in or out from the updates check mechanism would be a more reasonable implementation that would meet F-Droid's inclusion criteria.

The app should also clarify in this dialog and the settings menu, from where is the information extracted and APK downloaded from.

This a follow up from issue #262. @IzzySoft Let me know if I missed something, thanks!

Other details

No response

Acknowledgements

• I have searched the existing issues and this is a new ticket, NOT a duplicate or related to another open issue.
• I have written a short but informative title.
• I will fill out all of the requested information in this form.

[ishanvaghani]

I can work on this

[Artx-II]

Done with commit 372cb4d