app_queue: (Breaking change) shared_lastcall and autofill default to no

If your queues.conf had _no_ [general] section, they would default to
'yes'. Now, they always default to 'no'.

(Actually, commit ed615afb already
partially fixed it for shared_lastcall.)

ASTERISK-28951

Change-Id: Ic39d8a0202906bc454194368bbfbae62990fe5f6