AU: Ensure that Final Cut Pro will re-query the state information of the AudioProcessor when `updateHostDisplay` is called

modules/juce_audio_plugin_client/AU/juce_AU_Wrapper.mm

@@ -1084,6 +1084,7 @@ public:
         PropertyChanged (kAudioUnitProperty_Latency,       kAudioUnitScope_Global, 0);
         PropertyChanged (kAudioUnitProperty_ParameterList, kAudioUnitScope_Global, 0);
         PropertyChanged (kAudioUnitProperty_ParameterInfo, kAudioUnitScope_Global, 0);
+        PropertyChanged (kAudioUnitProperty_ClassInfo,     kAudioUnitScope_Global, 0);
 
         refreshCurrentPreset();