Add workflow for requests to update email contact associated with generated license

Why is this change being made?

I have encountered a couple of such requests to change email contact associated with a generated license as the listed contact is either invalid or no longer in the organization: (Internal Zendesk links)

• https://gitlab.zendesk.com/agent/tickets/297386
• https://gitlab.zendesk.com/agent/tickets/305000

Our workflows currently do not include such ticket instances, and how to handle them.
This MR seeeks to do that, based on the responses in prior tickets.

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