Fix missing drawIconsEnabled parameter initialization in the copying constructor of the ChartBaseDataSet (#4424)

Source/Charts/Data/Implementations/ChartBaseDataSet.swift

@@ -404,7 +404,7 @@ open class ChartBaseDataSet: NSObject, ChartDataSetProtocol, NSCopying
         copy.formLineDashPhase = formLineDashPhase
         copy.formLineDashLengths = formLineDashLengths
         copy.drawValuesEnabled = drawValuesEnabled
-        copy.drawValuesEnabled = drawValuesEnabled
+        copy.drawIconsEnabled = drawIconsEnabled
         copy.iconsOffset = iconsOffset
         copy.visible = visible