UnassignRole
Unassign a role from a specific user.
Parameters
ctx -  The context of the request.
unassignedRole - An object that contains the information about the role. The payload is defined below.
Payload
ctx -  The context of the request.
userKey - The key of the user to assign the role to.
roleKey - The key of the role to assign to the user.
tenantKey - The key of the user's tenant.
Implementation
	user, err := Permit.Api.Users.UnasignRole(ctx, "user-key", "role-key", "tenant-key")