Docker Windows container for Pester Tests

I recently wrote an intro to unit testing your powershell modules with Pester, and I wanted to give a walk through for our method of running these unit tests inside of a Docker for Windows container.

Unit Testing PowerShell Modules with Pester

Pester is a unit testing framework for Powershell. There are some good tutorials for it on their github page, and a few other places, but I'd like to pull together some of the key motivating use cases I've found and a couple of the gotchas.