functional tests: Return from a goroutine when the ACI server closes
functional tests: Return from a goroutine when the ACI server closes

The test ACI server closes both Msg and Stop channels on Close(). The
Stop channel never receives any messages - it is only used to listen
for service shutdown. The channel listening is done in serverHandler,
which is run in its own goroutine. The Stop channel was used shortly
before, but I wrongly removed it during review process. Because of
that, the function never returned and the goroutine was unnecessarily
kept alive.

blixtra/rkt,sstabellini/rkt,cab105/rkt,nhlfr/rkt,rkt/rkt,jzelinskie/rkt,markllama/rkt,Shashwatsh/rkt,il9ue/rkt,joshix/rkt,Shashwatsh/rkt,lucasallan/rkt,kinvolk/rkt,tmrts/rkt,coreos/rkt,lucasallan/rkt,endocode/rkt,monstermunchkin/rkt,yifan-gu/rocket,coreos/rkt,sinfomicien/rkt,sgotti/rkt,matthaias/rkt,achanda/rkt,kinvolk/rkt,adfernandes/rkt,dgonyeo/rkt,liugenping/rkt,adfernandes/rkt,jakon89/rkt,s-urbaniak/rkt,akshaykarle/rkt,markllama/rkt,cab105/rkt,mike1729/rkt,jjlakis/rkt,matthaias/rkt,tmrts/rkt,coreos/rkt,joshix/rkt,jonboulle/rkt,liugenping/rkt,sstabellini/rkt,shobhit85/rkt,endocode/rkt,achanda/rkt,squeed/rkt,ybubnov/rkt,s-urbaniak/rkt,Shashwatsh/rkt,jakon89/rkt,nhlfr/rkt,monstermunchkin/rkt,il9ue/rkt,squeed/rkt,yifan-gu/rocket,jzelinskie/rkt,alban/rkt,mike1729/rkt,tmrts/rkt,kbrwn/rkt,matthaias/rkt,ybubnov/rkt,yifan-gu/rkt,krnowak/rkt,Wilybald/rkt,liugenping/rkt,blixtra/rkt,yifan-gu/rocket,yifan-gu/rkt,jonboulle/rkt,linki/rkt,linki/rkt,euank/rkt,jzelinskie/rkt,Wilybald/rkt,sgotti/rkt,achanda/rkt,jjlakis/rkt,rkt/rkt,nhlfr/rkt,jasonchaffee/rkt,jjlakis/rkt,shobhit85/rkt,euank/rkt,linki/rkt,il9ue/rkt,monstermunchkin/rkt,dgonyeo/rkt,s-urbaniak/rkt,sgotti/rkt,kbrwn/rkt,dgonyeo/rkt,blixtra/rkt,kinvolk/rkt,joshix/rkt,sinfomicien/rkt,ybubnov/rkt,Wilybald/rkt,alban/rkt,lucasallan/rkt,lucasallan/rkt,intelsdi-x/rkt,cab105/rkt,akshaykarle/rkt,akshaykarle/rkt,sstabellini/rkt,intelsdi-x/rkt,Wilybald/rkt,krnowak/rkt,markllama/rkt,intelsdi-x/rkt,rkt/rkt,kinvolk/rkt,euank/rkt,shobhit85/rkt,jakon89/rkt,kbrwn/rkt,yifan-gu/rkt,joshix/rkt,mike1729/rkt,endocode/rkt,alban/rkt,sinfomicien/rkt,jonboulle/rkt,squeed/rkt,rkt/rkt,jasonchaffee/rkt,krnowak/rkt,adfernandes/rkt,jasonchaffee/rkt