Avoid 'Eureka' settings crash when servers have changed and app is not in foreground (#3413)

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Pending on #3412
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Documentation: home-assistant/companion.home-assistant#

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Author: bgoncal

Sources/App/Settings/SettingsViewController.swift

@@ -34,6 +34,7 @@ class SettingsViewController: HAFormViewController {
             }
 
             func serversDidChange(_ serverManager: ServerManager) {
+                guard UIApplication.shared.applicationState == .active else { return }
                 UIView.performWithoutAnimation {
                     updateRows()
                 }