C#: Remove reference to stageStats.

Author: aschackmull

csharp/ql/lib/semmle/code/csharp/dataflow/internal/ContentDataFlow.qll

@@ -16,8 +16,7 @@ module ContentDataFlow {
 
   class ContentSet = DF::ContentSet;
 
-  predicate stageStats = DF::stageStats/8;
-
+  // predicate stageStats = DF::stageStats/8;
   /**
    * A configuration of interprocedural data flow analysis. This defines
    * sources, sinks, and any other configurable aspect of the analysis. Each