Description of problem: Beaker API providing a way to change task status (Running, Completed, Aborted). However, if the task status is confirmed we lock this state from further change. For example Aborted can not be transferred back to Completed. Internally we are rising this error but we are not passing this into a client. Instead of that, we are firing 500 and clients don't know how to handle it. Version-Release number of selected component (if applicable): 26.6 Steps to Reproduce: 1. Run task in Beaker 2. Fire request to API to change the status to Completed (in case current status is running) 3. Fire another request to API Actual results: 500, Internal Server Error Expected results: 409, <Put here cool error message> Additional info: