fix flaky testcases/t/185-scratchpad.t: sync after kill command
fix flaky testcases/t/185-scratchpad.t: sync after kill command

stapelberg/i3,Airblader/i3,i3/i3,Airblader/i3,Airblader/i3,i3/i3,Airblader/i3,stapelberg/i3,i3/i3,stapelberg/i3,stapelberg/i3,i3/i3