Run tests on Linux using Cosmos DB emulator docker container

[philnach]

Feature Request: Run tests on Linux using Cosmos DB emulator docker container

Overview:
Currently today tests are run on Windows. DMT is available on Linux and MacOS, for people working on Linux they can leverage the docker container image of the Cosmos DB emulator to do local testing and development. DMT should verify that DMT works with the emulator on Linux.

Features:

1. New workflow added to run Linux tests
2. Workflow runs on Linux
3. Workflow downloads and sets up Cosmos DB emulator docker container for Linux
4. Workflow runs unit tests on Linux targeting the Cosmos DB Emulator running in docker container.