Closes #13334: Record error message on failed jobs

[jeremystretch]

Fixes: #13334

• Add an optional error text field on Job
• Extend the terminate() method to support passing an error message for failed jobs
• Update calls to Job.terminate() to pass error message where applicable

[arthanson]

Q: Would there be any security implications to this as showing the error would include traceback info. Would we want a permission to show this info on the job results at all? Probably not, but just wanted to mention it.

[jeremystretch]

AFAICT the error just includes the error message tied to the exception itself; it shouldn't include a traceback with it.