Remove old (no longer in existence) detected Autoupload Folders

### Is your feature request related to a problem? Please describe.
After installing an app (ie another camera app), NC Client finds the folder that the camera app used to store photos (nice, thanks).
I don't like the app, so uninstall it and manually delete the folder that it used.
I cannot remove that folder from the autoupload list within NC Client

I can see from other phones that NC Client has created sync points for Twitter, Instagram, Facebook (etc), where they would never want to upload those entries to NC

### Describe the solution you'd like
Allow autoupload to remove / delete a sync point (especially if that folder doesn't exist).

### Describe alternatives you've considered
"Hiding" the folder, which - (for others, this means hiding ~10 folders) - unknown is what that is doing internally (ie continuous errors retrying to find the folder?)

### Additional context
Android App v3.15.1