AthenaCommon: Don't add a duplicate ToolSvc to svcMgr.

ToolSvc is already set up in AppMgr.py; don't try to do it again
in AtlasUnixStandardJob.py, or we can get duplicate errors from Configurable.

Control/AthenaCommon/python/AtlasUnixStandardJob.py

@@ -19,7 +19,7 @@ def _setupAtlasUnixStandardJob():
     svcMgr += GaudiSvcConf.EvtPersistencySvc( "EventPersistencySvc" )
     svcMgr += GaudiSvcConf.HistogramSvc( "HistogramDataSvc" )
     svcMgr += GaudiSvcConf.NTupleSvc()
-    svcMgr += GaudiSvcConf.ToolSvc()
+    # ToolSvc is already added in AppMgr.py.
     svcMgr += GaudiSvcConf.RndmGenSvc()
     svcMgr += GaudiSvcConf.ChronoStatSvc()