Add better error handling for 'unhandled error exceptions'

When using AHA to integrate with other platforms such as Jira, sometimes fields are not mapped correctly due to either changes in Jira or custom fields in AHA. When this mismatch happens, we are only presented with 'unhandled error exception. Please contact AHA support'. There is no other indication of why the linking failed.

I have had to do this a couple of times now and it seems like a waste of time for AHA support when the issue is usually pretty straight forward to resolve.

I think support cases could be reduced (at least for this use case) if better error handling was shown to the user when scenarios like this are encountered so we can work with AHA/Jira admins to resolve the issue on our own.