[iOS][EarlGrey]Run tests quickly

Small, small tips to enhance conducting speed for EarlGrey.
In many cases, iOS can’t handle animation speed such as Android even UI Test cases.

EarlGrey available changing animation speed except for UIScrollView. here

// Swift
let kMaxAnimationInterval: CFTimeInterval = 5.0
GREYConfiguration.sharedInstance().setValue(kMaxAnimationInterval, forConfigKey: kGREYConfigKeyCALayerMaxAnimationDuration)

// Swift
GREYTestHelper.enableFastAnimation()

https://github.com/google/EarlGrey/blob/master/docs/faq.md

In XCUITest case:

# swift
UIApplication.sharedApplication.keyWindow.layer.speed = 100