Only prompt for location access on the Onboarding screen if no locations are set up.

1Weather/UI/View controllers/Onboarding/OnboardingViewController.swift

@@ -30,7 +30,9 @@ class OnboardingViewController: UIViewController {
     override func viewDidAppear(_ animated: Bool) {
         super.viewDidAppear(animated)
         closing = false
-        promptForLocationAccess()
+        if !locationManager.hasLocations {
+            promptForLocationAccess()
+        }
     }
     
     var closing = false