test: Multiprocess tests can now be configured via a web service and run on Windows and Mac clients.

[zain-mecklai]

Since many platforms either don't take command line arguments or don't handle them in quite the same way the remote clients launched by the test need to be configured consistently, thus the webservice is used to configure them. Right now the key to matching the test runner to the client is just the githash but this will need to change to be more specific as it is possible to have the same githash being run in multiple different places. This will be addressed in a future PR.

Changelog

Nothing changed in the product so N/A for changelog

Testing and Documentation

• No new tests were added
• Existing multiprocess tests should now be runnable on a Windows or Mac remote client (more platforms to be supported in future PRs)

Deprecated API

• N/A