AudioProcessor: Only warn once if any parameter version hint is zero

modules/juce_audio_processors/processors/juce_AudioProcessor.cpp

@@ -437,7 +437,9 @@ void AudioProcessor::validateParameter (AudioProcessorParameter* param)
         See the documentation for AudioProcessorParameter(int) for more information.
     */
    #if JucePlugin_Build_AU
-    jassert (wrapperType == wrapperType_Undefined || param->getVersionHint() != 0);
+    static std::once_flag flag;
+    if (wrapperType == wrapperType_Undefined || param->getVersionHint() != 0)
+        std::call_once (flag, [] { jassertfalse; });
    #endif
 }