Trivial Description
When a user attempts to create a job that exceeds their quota, a response is returned that looks like this:
"INFO] Response from scheduler: INVALID_REQUEST (message: Insufficient resource quota: Optional.of(CPU quota exceeded by 4.00 core(s); RAM quota exceeded by 6144.00 MB; DISK quota exceeded by 2048.00 MB))"
The "Optional.of" wrapper is an implementation detail, and the contents should be unwrapped when the scheduler creates that message.