Refactor PHPUnit mock assertions to use Mockery

[phavekes]

This issue is imported from pivotal - Originaly created at Nov 25, 2019 by Michiel Kodde

EngineBlock is a project that spans several decades of PHP testing developments. And you can see that from the testing tools utilized. For example we use 3 different mock testing tools.

1. PHPUnit Mock
2. Mockery
3. Prophecy

This is not a bad thing per se as each tool has its pro's and cons. This story should identify which tool is used for what reason. And when opportune, rewrite the test to use the mock testing tool of our choosing.

Left-over from:
#168924689