fix(echarts): pass vizType to enable theme overrides in all chart types (#36389)

superset-frontend/plugins/plugin-chart-echarts/src/BigNumber/BigNumberViz.tsx

@@ -379,6 +379,7 @@ function BigNumberVis({
           height={maxHeight}
           echartOptions={echartOptions}
           eventHandlers={eventHandlers}
+          vizType={formData?.vizType}
         />
       )
     );