Create User dialog no longer automatically suggests username based on first and last names

Note that the completion still works when you enter the first name and last name before entering the user name. But I agree with you that it's kind of a usability regression. See also the chat where I discussed this with Thiago Krieck and he considered the change okay.

See also the proposal that was done on the forum about the changes: https://forum.xwiki.org/t/proposal-for-a-better-registration-process/13805 apparently the idea from Thiago Krieck was that the username field is required while first/last name are not, hence the move.

Note: I changed the priority as blocker, because you labelled as a regression and per our rules, any regression is a blocker and should get priority. But we might change again its priority depending how we handle it.