remove of job chain nodes will cause a broken job_chain

Current Situation

• Removing a job chain node in a job chain will cause a broken job chain, because the next state of the previous node still points to the removed job chain node.

Desired Behavior

• JOE should adjust the next state and error state of any job nodes that refer to the removed job node to point to the job nodes that the removed job node referred to for the next state and for the error state.