Allow users to update other fields during transition.

[jpavlav]

We have need of the ability to set the resolution of a ticket when we are transitioning it to a Done state. This should do the trick. For reference:

https://github.com/pycontribs/jira/blob/3a630c5f1c771fb27b407860d684da879d14e622/jira/client.py#L2557

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