[SPARK-2208] Fix for local metrics tests can fail on fast machines

## What changes were proposed in this pull request?

A fix for local metrics tests that can fail on fast machines.
This is probably what is suggested here #3380 by aarondav?

## How was this patch tested?

CI Tests

Cheers

Author: Joan <joan@goyeau.com>

Closes #11747 from joan38/SPARK-2208-Local-metrics-tests.