Update Custom Metrics / Performance Measure with Trend param isTime == true

[dirtydiesel46]

Add isTime == true param to Trends
Fixed value being added to the myTrend trend too

What?

1. The documentation isn't declaring the trend metric as a time based trend metric

Documentation shows

const myTrend = new Trend('total_action_time');

and not

const myTrend = new Trend('total_action_time',true);

2. Passed correct value to the add method of Trend

Documentation shows

myTrend.add(total_action_time);

should be

myTrend.add(totalActionTime);

4. The results that has a missing s has been added, it's supposed to be a time based metric

Documentation shows

  iteration_duration..........: avg=1.06s    min=1.06s    med=1.06s    max=1.06s    p(90)=1.06s    p(95)=1.06s
  iterations..................: 1      0.70866/s
  total_action_time.............: avg=295.3    min=295.3    med=295.3    max=295.3    p(90)=295.3    p(95)=295.3

and not

  iteration_duration..........: avg=1.06s    min=1.06s    med=1.06s    max=1.06s    p(90)=1.06s    p(95)=1.06s
  iterations..................: 1      0.70866/s
  total_action_time.............: avg=295.3s    min=295.3s    med=295.3s    max=295.3s    p(90)=295.3s    p(95)=295.3s

Checklist

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Related PR(s)/Issue(s)

[CLAassistant]

All committers have signed the CLA.

[mdcruz]

Thank you, Daniel! Just one minor comment :)

[mdcruz]

Just ran the test locally, and I've updated the time from s to ms to reflect it accurately.