CSS setstylesheetproperty value converter uses px instead of %

[ustk]

@Christoph-Hart The CSS value converter of laf.setStyleSheetProperty("myProperty", 0.5, "%"); results in 0.5px instead of 50%

https://docs.hise.dev/scripting/scripting-api/scriptlookandfeel/index.html#setstylesheetproperty