field_group_delete_user uses wrong route

I couldn't reproduce it in RC3

I just experienced this issue exactly as it is describe in the issue summary using the rc4 release. If you need other information, please let me know on here. It seems that the error should be able to be replicated simply by downloading the rc4 release, and some fields to User, and then adding a fieldgroup on the User>Form Display page and then clicking 'Save'.

Tried to reproduce this, but everything is working here. I followed same steps, on a clean drupal 8 site.

The route field_ui.field_group_delete_user, should exist, as a route is created for every fieldable entity type on the site.
So unless another module is blocking the 'alter routes' event, this should work.

Closing this as duplicate of #2645616. Found the problem, the fix should be committed this evening.

@zuuperman Thanks! I really appreciate your efforts on this. I'm not using field_group on a d8 site right now, but I'm sure that I will use it sometime in the coming months. If you need more specific information from me to reproduce the issue, let me know.