PyDumper: Fix problem with pixel configuration

If we run the event dump job configuration, it was crashing
because PixelDCSCondHVAlg was being added to the conditions sequence
without the stuff it depends on.  However, we don't need any of that
stuff at all here; we can suppress it by enabling the doAODMerging flag.
So do that.

(Eventually should change this to the new job configuration...)

Event/PyDumper/python/SgDumpLib.py

-# Copyright (C) 2002-2019 CERN for the benefit of the ATLAS collaboration
+# Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 
 # @file    PyDumper.SgDumpLib
 # @purpose API for the sg-dump script
@@ -87,6 +87,9 @@ def _gen_jobo(dct):
                      ):
             getattr (rec, item).set_Value_and_Lock(False)
 
+        # Disables more stuff we don't need.
+        rec.doAODMerging.set_Value_and_Lock(True)
+
         # events to process
         acf.EvtMax = %(evts)s
         acf.SkipEvents = %(skip)s