JUCE no longer depends on built artifacts of the AAX_SDK

Opening some JUCE VST3s in FL Studio's patcher can cause crashes because
of data races on objects accessed from setActive() and process().

According to the VST3 specification, these functions should never be
called simultaneously, so I think this is a bug in FL Studio.

This can be tested by toggling 'Distortion' on and off in the
DSPModulePluginDemo, and checking the latency reported in the node
statistics in AUM.

This is a breaking change - see BREAKING-CHANGES.txt

This change fixes an issue where the program list was not populated in
Cubase 12.