Dockerfile-test: add "alexkohler/nakedret"
Dockerfile-test: add "alexkohler/nakedret"

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

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