Update SignedBinaryProxyExecutionRundll32.yaml

Hunting Queries/SecurityEvent/SignedBinaryProxyExecutionRundll32.yaml

@@ -21,7 +21,7 @@ query: |
   | extend EventData = parse_xml(EventData).DataItem.EventData.Data
   | mv-expand bagexpansion=array EventData
   | evaluate bag_unpack(EventData)
-  | extend Key=tostring(['@Name']), Value=['#text']
+  | extend Key = tostring(column_ifexists('@Name', "")), Value = column_ifexists('#text', "")
   | evaluate pivot(Key, any(Value), TimeGenerated, Source, EventLog, Computer, EventLevel, EventLevelName, EventID, UserName, RenderedDescription, MG, ManagementGroupName, Type, _ResourceId)
   | extend RuleName = column_ifexists("RuleName", ""), TechniqueId = column_ifexists("TechniqueId", ""),  TechniqueName = column_ifexists("TechniqueName", "")
   | parse RuleName with * 'technique_id=' TechniqueId ',' * 'technique_name=' TechniqueName