Give a better message upon jira search failure

Instead of a traceback we now provide a reasonable message like this:

 Failed to fetch jira issues for query 'issueFunction in commented('by
 nonexistent after 2021-09-20 before 2021-09-27')'. The reason was 'Bad
 Request' and the error was 'Cannot find user with username: nonexistent.
 The argument should be in the form ("by jbloggs"), or any of ("by jbloggs
 on Date after Date before Date inRole Role inGroup Group roleLevel Role
 groupLevel Group"). Date can be either a date or an expression like -5d or
 -8w, or a function like startOfMonth().'.

psss / did

Give a better message upon jira search failure #248