latency和responseTime的单位需要在文档明确一下为us

[Minnull]

latency, time consuming in nebula server.
responseTime, time consuming in client.
两个指标为封装k6后的自定义指标，需要明确在文档明确一下为us单位

[HarrisChu]

should change latency to latencyInUs

[HarrisChu]

refer:https://github.com/vesoft-inc/k6-plugin/blob/master/example/nebula-test-insert.js

var latencyTrend = new Trend('latency', true);
var responseTrend = new Trend('responseTime', true);

and then the metrics could be time with unit