add documentation for group by array based result format (#8416)
add documentation for group by array based result format (#8416)


druid-io/druid,gianm/druid,mghosh4/druid,pjain1/druid,pjain1/druid,implydata/druid,nishantmonu51/druid,leventov/druid,michaelschiff/druid,nishantmonu51/druid,himanshug/druid,druid-io/druid,pjain1/druid,himanshug/druid,Fokko/druid,Fokko/druid,michaelschiff/druid,deltaprojects/druid,pjain1/druid,monetate/druid,monetate/druid,jon-wei/druid,mghosh4/druid,jon-wei/druid,Fokko/druid,deltaprojects/druid,michaelschiff/druid,deltaprojects/druid,pjain1/druid,pjain1/druid,nishantmonu51/druid,implydata/druid,nishantmonu51/druid,gianm/druid,michaelschiff/druid,deltaprojects/druid,pjain1/druid,mghosh4/druid,leventov/druid,jon-wei/druid,implydata/druid,jon-wei/druid,leventov/druid,deltaprojects/druid,nishantmonu51/druid,michaelschiff/druid,himanshug/druid,jon-wei/druid,gianm/druid,himanshug/druid,jon-wei/druid,nishantmonu51/druid,leventov/druid,gianm/druid,monetate/druid,gianm/druid,implydata/druid,Fokko/druid,mghosh4/druid,monetate/druid,druid-io/druid,implydata/druid,deltaprojects/druid,druid-io/druid,jon-wei/druid,mghosh4/druid,gianm/druid,michaelschiff/druid,implydata/druid,druid-io/druid,himanshug/druid,Fokko/druid,michaelschiff/druid,mghosh4/druid,Fokko/druid,Fokko/druid,mghosh4/druid,nishantmonu51/druid,deltaprojects/druid,monetate/druid,monetate/druid,gianm/druid,monetate/druid,leventov/druid