CATROID-1071 GoToRandomPositionAction refactor

[erikcoxx98]

Refactor GoToRandomPositionAction.java and GoToRandomPositionActionTest.java to Kotlin - Ticket 1071

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[JayTropper]

I would prefer, if all the three variables would be initialized with the lateinit key word as follows:

Suggested change

	private var sprite: Sprite? = null
	private lateinit var sprite: Sprite

Gives the code a cleaner look, since we you can then remove all the !! operators from the method calls.

[JayTropper]

Please replace all Assert.assertEquals() with the simple assertEquals() from junit.framework.TestCase.assertEquals, since it is deprecated.