test: Add test cases for `Echarts.DataTool.loadDataTool` and update implement for `Echarts`'s test case
test: Add test cases for `Echarts.DataTool.loadDataTool` and update implement for `Echarts`'s test case

Pluto-Y/SwiftyEcharts,Pluto-Y/SwiftyEcharts,Pluto-Y/SwiftyEcharts