QmlDesigner: Fix puppet crash with nested Repeater3Ds

Repeater3D instance instantiated by another Repeater3D got its
componentCompleted called twice because a repeater constructing a
child repeater already completes the component as part of the process,
and then we recursively complete the children again when completing
the parent. Added a check to avoid duplicate completions.

Fixes: QDS-5651
Change-Id: Iefc7deff4877df903f784396f2efd13468f604b7
Reviewed-by: Samuel Ghinet <samuel.ghinet@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

share/qtcreator/qml/qmlpuppet/qmlprivategate/qmlprivategate_56.cpp

@@ -61,6 +61,10 @@
 #include <private/qqmlmetatype_p.h>
 #include <private/qqmltimer_p.h>
 
+#ifdef QUICK3D_MODULE
+#include <private/qquick3dobject_p.h>
+#endif
+
 namespace QmlDesigner {
 
 namespace Internal {
@@ -374,6 +378,11 @@ void doComponentCompleteRecursive(QObject *object, NodeInstanceServer *nodeInsta
 
         if (item && DesignerSupport::isComponentComplete(item))
             return;
+#ifdef QUICK3D_MODULE
+        auto obj3d = qobject_cast<QQuick3DObject *>(object);
+        if (obj3d && QQuick3DObjectPrivate::get(obj3d)->componentComplete)
+            return;
+#endif
 
         if (!nodeInstanceServer->hasInstanceForObject(item))
             emitComponentComplete(object);