iOS: Remove simulator management from settings page

Simulators can be managed via Xcode, which must be installed anyway. Re-
implementing this functionality is not useful, error-prone, and a
maintenance burden. Point users to the corresponding Xcode documentation
instead.

Add a button for updating the list of simulators in the run configuration
settings (which didn't update when simulators were changed in Xcode).

Change-Id: I5a861f21851bb866d45a703f46bb20ed5df960e8
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>

src/plugins/ios/iosrunconfiguration.h

@@ -3,8 +3,6 @@
 
 #pragma once
 
-#include "iosconstants.h"
-#include "iosconfigurations.h"
 #include "iossimulator.h"
 
 #include <projectexplorer/runconfiguration.h>
@@ -12,9 +10,13 @@
 
 #include <utils/fileutils.h>
 
-#include <QComboBox>
 #include <QStandardItemModel>
 
+QT_BEGIN_NAMESPACE
+class QComboBox;
+class QPushButton;
+QT_END_NAMESPACE
+
 namespace Ios::Internal {
 
 class IosRunConfiguration;
@@ -58,6 +60,7 @@ private:
     QStandardItemModel m_deviceTypeModel;
     QLabel *m_deviceTypeLabel = nullptr;
     QComboBox *m_deviceTypeComboBox = nullptr;
+    QPushButton *m_updateButton = nullptr;
 };
 
 class IosRunConfiguration : public ProjectExplorer::RunConfiguration