[QA] zend → php53 in CI config

[Legoktm]

On 01/19/2016 07:33 AM, Antoine Musso wrote:
> Thank you Kunal to have driven that effort :-}
> 
> From my review yesterday, I guess you can safely delete the old jobs and
> workspaces.  If something wrong happens, we can always adjust the
> related Zuul layout.

I deleted the jobs and workspaces on Tuesday, haven't seen anything go
wrong so far. :)

-- Legoktm