Clarify Email when Approver is set
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### Problem to solve
Currently, the email that is sent after a user is set as an approver does not clarify that there is action required.
### Further details

### Proposal
Let the approver know what there is action needed on their part.
### What does success look like, and how can we measure that?
The email is clear that the user has been set as an approver and that action is required on their part.
### Links / references
Customer ticket -> https://gitlab.zendesk.com/agent/tickets/102686 (internal use)
issue