DDC-1550: GH-234: Fix QueryTest#testJoinQueries order

[doctrinebot]

Jira issue originally created by user @beberlei:

Pull-Request was automatically synchronized: #234

I don't know why, but sometimes postgres change the order by column default.

http://travis-ci.org/#!/doctrine/doctrine2/jobs/428335

I just add ORDER BY, I think that fix the problem.

[doctrinebot]

Issue was closed with resolution "Fixed"

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-234] was closed:
doctrine/common#234