Group order reset after adding a new group

[aqurilla]

This fixes #10017 by removing the sort that was being carried out after group addition and edit

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[HoussemNasri]

With this PR merged, we're gonna have to reopen koppor#577. A more sophisticated solution would be to make the sort menu item a check box item, that way when a group is added, we sort subgroups when the sort menu item is checked and keep the same order when it's not.

I think we should merge this PR because it introduces a slightly better behavior (you can sort the groups manually after adding a new group, but you can't go back to the previous order if sorting is done automatically) than the current one until we have a proper solution in place.