Bug#881086: qastools: diff for NMU version 0.21.0-1.1

[Sebastian Holtermann]

> Dear maintainer,
> 
> I've prepared an NMU for qastools (versioned as 0.21.0-1.1) and uploaded 
> it to DELAYED/10 Please feel free to tell me if I should cancel it.

This looks like a small fix and I'm too busy right now. Please go ahead.

-Sebastian