GDPR - Enhance remove role button functionality

[Tribunal33]

Description:
During our meeting we discussed how to handle the remove role button for both the new invite to a role flow and the edit existing user flow. I think the solution will be valid for both scenarios.

Steps to test the changes:

1. Test invite user to a role, existing user
2. Test invite user to a role, new user
3. Test edit existing user from user table

Solution: Remove role button should always be displayed.
Scenario 1 : Invite to a role
Requirement 1 : If an existing user is invited the first row will be the already accepted roles.
Requirement 2 : A row for adding a new role will be displayed with empty fields and the Remove role button.
Requirement 3 : If the user selects remove role and it is the first role to be added then the button will clear all the fields
Requirement 4: If the Add New Role button is selected then a new row will appear and a remove role button will be displayed.
Requirement 5: If the Remove Role button is selected and it is not the first newly added role row it will be deleted from the list.

Scenario 2: Edit existing user
Requirement 1 : Existing user is invited the first row will be the already accepted roles.
Requirement 2 : No other rows are added until the user selects Add new Role button
Requirement 3 : After selecting Add New Role button a new row will be displayed with empty fields and Remove Role button
Requirement 4: If the user selects remove role and it is the first role to be added then the button will clear all the fields
Requirement 5: If the Add New Role button is selected then a new row will appear and a remove role button will be displayed.
Requirement 6: If the Remove Role button is selected and it is not the first newly added role row it will be deleted from the list.

Scenario 3: Edit existing user and remove last role associated with the user
Requirement 1: When removing the last existing role from a user this will be blocked
Requirement 2: When this role is blocked a warning message is displayed "You need to select at least one role to be associated with this user"
Requirement 3: The role will not be removed until there is at least one role associated with this user. This means that an invitation to a role does not count towards determining if the role can be removed.
What application are you using?
OJS hybrid 3.4/3.5 GDPR Craft-OA 9658 branch

Additional information
This will fix the PART 2 issue from #11020

[withanage]

@Tribunal33 this is ready for testing

[Tribunal33]

This passes QA. Tests added to regression suite.

[Tribunal33]

I have re-opened this issue as there was one more scenario to cover when removing the last remaining accepted role. Previously in 3.4 there would be a warning that would prevent removing the last accepted role.