Replace some more "command -v" calls with the Helper method

Remove some more output mid-unittests on windows.

Second part from #12303 

@MorrisJobke @icewind1991 @LukasReschke 
This was regarding the return value of `checkDependencies` it could return nothing or `array('smbclient')` instead of `true` and `array('smbclient')`