beta: adapt $wgParsoidCacheServers

dan-nl noticed in logs/runJobs.log several of the following connection
timeouts:

    2013-12-10 23:50:25 deployment-jobrunner08 enwiki:
    ParsoidCacheUpdateJobOnEdit Latex
    type=OnEdit t=126317 error=Failed connect to 10.2.2.29:80;
    Connection timed out

Gabriel Wicked noted that $wgParsoidCacheServers needs to be updated for
beta and be made to point to the varnish cache.

bug: 58300
Change-Id: I630548c74a04035f6fbe279c2801fa5024d2612d