Remove guest groups from the internal space permissions

Summary

As a space administrator, when trying to search for guest users under the Internal users, it will not display the user, which is great. However, when searching for a group under the Internal groups part, it will display the guest groups.

However, as soon as the group is attempted to be added, the following error message is displayed:

GROUP_X is a guest group and cannot be added as an internal group.

Suggestion

This is a suggestion to not display guest groups under the search for space permissions. Although they cannot be added, this could help avoiding confusion.