https://github.com/jenkinsci/echarts-api-plugin/blob/main/src/main/resources/charts/trend-chart.jelly#L46-L51
jenkinsci/echarts-api-plugin/pull/357
Fixed in jenkinsci/echarts-api-plugin#357. Released in 5.5.1-2.
Fixed in jenkinsci/echarts-api-plugin#357. Released in 5.5.1-2.