iOS: Fix a constant redrawing bug

modules/juce_gui_basics/native/juce_UIViewComponentPeer_ios.mm

@@ -2198,6 +2198,8 @@ void UIViewComponentPeer::displayLinkCallback()
 
     for (const auto& r : deferredRepaints)
         [view setNeedsDisplayInRect: convertToCGRect (r)];
+
+    deferredRepaints.clear();
 }
 
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