Remove unnecessary db request

We have no db server on the build server.
When I had tryed to collect static I saw this error:
    django.db.utils.OperationalError: could not connect to server: Connection refused
    	Is the server running on host "127.0.0.1" and accepting
    	TCP/IP connections on port 5432?
Full stacktrace: http://pastebin.com/xx7Te8HS
This fix will remove useless query to database server.