make_master_server uncached again!

https://bugzilla.redhat.com/show_bug.cgi?id=1402943

We lock on the region row and base all of our server is_master
queries and changes on it, therefore, it's really important we don't
have a cached region.

app/models/miq_server/server_monitor.rb

@@ -17,7 +17,7 @@ def mark_as_not_responding(seconds = miq_server_time_threshold)
 
   def make_master_server(last_master)
     _log.info "Master server has #{last_master.nil? ? "not been set" : "died, #{last_master.name}"}.  Attempting takeover as new master server, #{name}."
-    parent = MiqRegion.my_region
+    parent = MiqRegion.my_region(true)
     parent.lock do
       # See if an ACTIVE server has already taken over
       active_servers = parent.active_miq_servers