update: improve warning about APKs set to be debuggable
update: improve warning about APKs set to be debuggable

This uses the actual XML code used to set this flag making the warning
message easily searchable on the interwebs.

fdroidtravis/fdroidserver,fdroidtravis/fdroidserver,matlink/fdroidserver,f-droid/fdroidserver,OneEducation/AppUniverse_Server,fdroidtravis/fdroidserver,OneEducation/AppUniverse_Server,f-droid/fdroidserver,f-droid/fdroid-server,f-droid/fdroidserver,OneEducation/AppUniverse_Server,f-droid/fdroidserver,OneEducation/AppUniverse_Server,f-droid/fdroid-server,matlink/fdroidserver,fdroidtravis/fdroidserver,matlink/fdroidserver,matlink/fdroidserver,f-droid/fdroidserver,OneEducation/AppUniverse_Server,f-droid/fdroid-server,f-droid/fdroid-server,f-droid/fdroid-server,matlink/fdroidserver