Remove (some) bashisms from the test scripts

[Martin Schwenke]

On Thu, 4 Jan 2018 06:43:10 +0200, Uri Simchoni <uri at samba.org> wrote:

> The patch removes bashisms, not sh'isms :)
> 
> I'll add that if I'm the one to eventually push this fix.

:-)

Separate patch?  ;-)

peace & happiness,
martin