Add exponential backoff into test retrying mechanics

[maksym-zhokha]

What do you think about adding exponential backoff to existing RetryingTest functionality?

For example:
There is already suspendForMs which allows to put some constant time so that JUnit will wait this portion of time before running test again. By adding some exponential backoff (with base 2) JUnit will wait between second and third (if second test try also was failed) tries 2 x suspendForMs. Waiting for the next try will took 4 x suspendForMs.

[IlyasYOY]

This issue is heavily entangled with this one: #783

If both might be implemented I'd recommend to add some kind of IoC for suspension time.

We could add suspensionTimeProvider parameter, which takes class implementing SuspensionTimeProvider. The extension instantiates an object of this class using default no args constructor (or using SPI) and retrieves time interval by iteration number.