Only return usernames without any roles for autocomplete.
Only return usernames without any roles for autocomplete.

indirectlylit/kolibri,DXCanas/kolibri,benjaoming/kolibri,MingDai/kolibri,learningequality/kolibri,christianmemije/kolibri,MingDai/kolibri,DXCanas/kolibri,jonboiser/kolibri,christianmemije/kolibri,christianmemije/kolibri,indirectlylit/kolibri,lyw07/kolibri,indirectlylit/kolibri,lyw07/kolibri,DXCanas/kolibri,learningequality/kolibri,rtibbles/kolibri,indirectlylit/kolibri,christianmemije/kolibri,jonboiser/kolibri,rtibbles/kolibri,benjaoming/kolibri,mrpau/kolibri,mrpau/kolibri,benjaoming/kolibri,learningequality/kolibri,DXCanas/kolibri,MingDai/kolibri,rtibbles/kolibri,lyw07/kolibri,MingDai/kolibri,rtibbles/kolibri,lyw07/kolibri,jonboiser/kolibri,mrpau/kolibri,mrpau/kolibri,benjaoming/kolibri,jonboiser/kolibri,learningequality/kolibri