DLSV2-619 Supervisor promote staff to nominated supervisor

[kevwhitt-hee]

JIRA link

DLSV2-619

Description

Implements an interface for full Supervisors to promote members of their staff to the Nominated Supervisor role. This is available from the expanded staff card on the supervisor staff list for any member of staff who has "Learner" role. A confirmation screen is included and shares its view model with the similar remove staff member confirm screen.

Screenshots

Nominate supervisor button (for full supervisors only and for staff who are DLS role = learner only):

Confirmation page:

Confirm validation:

Nominated supervisor role granted:

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Developer checks

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I have:

• Run the formatter and made sure there are no IDE errors.
• Written tests for the changes (accessibility tests, unit tests for controller, data services, services, view models, etc)
• Manually tested my work with and without JavaScript. Full manual testing guidelines can be found here: https://softwiretech.atlassian.net/wiki/spaces/HEE/pages/6703648740/Testing
• Updated/added documentation in Swiki and/or Readme. Links (if any) are below:
  • doc_1_here
• Updated my Jira ticket with information about other parts of the system that were touched as part of the MR and have to be sanity tested to ensure nothing’s broken.
• Scanned over my own MR to ensure everything is as expected.