tests: simplify for loop conditions
tests: simplify for loop conditions

For loop invocation is simplified to comply with `gofmt -s`

jjlakis/rkt,sstabellini/rkt,tmrts/rkt,joshix/rkt,ybubnov/rkt,yifan-gu/rocket,lucasallan/rkt,mike1729/rkt,matthaias/rkt,yifan-gu/rkt,Wilybald/rkt,tmrts/rkt,tmrts/rkt,dgonyeo/rkt,joshix/rkt,euank/rkt,dgonyeo/rkt,Shashwatsh/rkt,nhlfr/rkt,ybubnov/rkt,kinvolk/rkt,shobhit85/rkt,achanda/rkt,kinvolk/rkt,monstermunchkin/rkt,Wilybald/rkt,jakon89/rkt,rkt/rkt,joshix/rkt,jjlakis/rkt,Shashwatsh/rkt,Wilybald/rkt,lucasallan/rkt,rkt/rkt,lucasallan/rkt,monstermunchkin/rkt,euank/rkt,yifan-gu/rocket,jjlakis/rkt,shobhit85/rkt,shobhit85/rkt,Wilybald/rkt,akshaykarle/rkt,intelsdi-x/rkt,sgotti/rkt,rkt/rkt,rkt/rkt,yifan-gu/rkt,nhlfr/rkt,sstabellini/rkt,jonboulle/rkt,sstabellini/rkt,intelsdi-x/rkt,squeed/rkt,euank/rkt,jonboulle/rkt,s-urbaniak/rkt,sgotti/rkt,sgotti/rkt,akshaykarle/rkt,kinvolk/rkt,s-urbaniak/rkt,joshix/rkt,mike1729/rkt,coreos/rkt,coreos/rkt,matthaias/rkt,yifan-gu/rocket,kinvolk/rkt,intelsdi-x/rkt,yifan-gu/rkt,alban/rkt,squeed/rkt,jonboulle/rkt,alban/rkt,mike1729/rkt,achanda/rkt,akshaykarle/rkt,jakon89/rkt,achanda/rkt,cab105/rkt,lucasallan/rkt,cab105/rkt,squeed/rkt,ybubnov/rkt,matthaias/rkt,jakon89/rkt,s-urbaniak/rkt,alban/rkt,dgonyeo/rkt,monstermunchkin/rkt,cab105/rkt,coreos/rkt,Shashwatsh/rkt,nhlfr/rkt