New Assemblies Can Be Added to SDK Without Precompilation

[brianrob]

Because there is no validation that SDK assemblies are pre-compiled, it is easy for new assemblies to be added that don't get pre-compiled.

This issue tracks the need to have a test that can catch these assemblies and give developers an opportunity to fix the issue before it becomes a performance regression.

[marcpopMSFT]

Old issue triage: closing as lower priority.