Dockerfile-test: add 'ineffassign' to image
Dockerfile-test: add 'ineffassign' to image

Was missing for 'fmt' tests.

Signed-off-by: Gyu-Ho Lee <3454051ee3341eb69bdf6fca40899cdad4d86496@gmail.com>

dannysauer/etcd,mkumatag/etcd,mqliang/etcd,etcd-io/etcd,etcd-io/etcd,akauppi/etcd,ajityagaty/etcd,gyuho/etcd,mqliang/etcd,sebrandon1/etcd,joshix/etcd,vimalk78/etcd,cockroachdb/etcd,dannysauer/etcd,xiang90/etcd,fanminshi/etcd,coreos/etcd,vimalk78/etcd,fanminshi/etcd,lorneli/etcd,glevand/coreos--etcd,sebrandon1/etcd,sinsharat/etcd,heyitsanthony/etcd,etcd-io/etcd,xiang90/etcd,coreos/etcd,joshix/etcd,lorneli/etcd,sinsharat/etcd,li-ang/etcd,ajityagaty/etcd,li-ang/etcd,mkumatag/etcd,whuwxl/etcd,whuwxl/etcd,bluebreezecf/etcd,rnaveiras/etcd,rnaveiras/etcd,rnaveiras/etcd,cockroachdb/etcd,glevand/coreos--etcd,bdarnell/etcd,mqliang/etcd,heyitsanthony/etcd,ajityagaty/etcd,bdarnell/etcd,akauppi/etcd,gyuho/etcd,mkumatag/etcd,bluebreezecf/etcd