User plugin issue labeling

[CD-Z]

This PR aims to create Labels for each plugin.
The reason for this is to force users to select the right plugin and get the issue labeled with the plugin id.
With this it will be possible to mark faulty plugins in the app with the help of an api call.
For example:

• https://api.github.com/repos/LNReader/lnreader-plugins/issues?labels=Source%20Request,Theme:%20Madara

That way it will be easier to reduce duplicate issues and also provide a direct link from the app to the open issues of a plugin.

Current progress:
[x] Dropdown with all plugin names (Can be viewed in my fork)
[x] Dropdown for issue severity
[x] Auto Issue labeling

[nyagami]

I think the format Plugin: <Plugin name>[Plugin id] looks better.
eg: Plugin: Hako[ln.hako]

[CD-Z]

True, but I think the label gets to long. Maybe just Plugin: {id}

[CD-Z]

I now changed the labels