Provide an easy way for the admins to remove group mappings

[trrenty]

Is your feature request related to a problem? Please describe or add steps to reproduce your use case.
We have the following scenario (ill use pseudo code for ldap filters):

1. The admin configured a filter for the ldap groups that should be mapped to xwiki groups: filter = class is Group
2. The admin runs the group import job that maps all the ldap groups to new xwiki groups, matching the names
3. The admin changes the filter to filter = class is Group AND name like 'Prefix*'
4. The admin deletes all the existing groups
5. The admin runs the group import job again

In this situation, when the user runs the group import job the second time, the ldap groups matching the initial filter are still getting imported. This is because the group mapping was not updated.

Describe the solution you'd like
It would be nice if the user had an easy way to update the group mappings in this situation.

A nice feature would be that, when the user deletes any xwiki group, any mapping that existed of the group should be deleted or at least have the user prompted on whether they want that or not.

Another possibility is that, when the user changes the filter, they could get prompted on what to do with the already imported and mapped groups. Maybe some kind of reset button for the mapping?

[snazare]

to check how it's handled in ad pro integration