[BE] Manager - I can assign a mentorable position to a user

[atoff]

Description:

A user should be able to be assigned permissions to request a session on a mentorable position

Acceptance Criteria / Requirements:

AC1: A user can have a mentorable position assigned to a specific user
AC2: A training manager can see which users are assigned to which mentorable positions

Additional context:

[Keanu73]

Should we implement a rank attribute in the GraphQL schema to specify what role a user is? Or should we do it based upon their ATC rating (e.g. I1, I3, etc)

[atoff]

@Keanu73 I'm not quite sure what you mean? This issue is for adding the API methods to add and remove a mentorable position to user (as added in PR #36), and a method to list mentorable positions with their users. At this stage, we aren't concered with permissions, as these will be defined at a later stage.

[Keanu73]

Alright, fair enough, was thinking a bit too outside the box there.