Agent-scheduler: metrics.UpdateE2eDuration are inaccurate

[yccharles]

Description

In function runOnce:

1. scheduleStartTime := time.Now()
2. schedCtx, err := worker.generateNextSchedulingContext() : get and wait for a pod.
3. metrics.UpdateE2eDuration(metrics.Duration(scheduleStartTime)) scheduleStartTime this time include wait time , not only scheduler time .

Steps to reproduce the issue

Describe the results you received and expected

expected: metrics.UpdateE2eDuration(dura) only incluster : 1. GetSnapshot time() 2. executeAction Time()

What version of Volcano are you using?

master

Any other relevant information

No response

[JesseStutler]

/assign