Merge pull request github#6394 from github/p0/csharp-virtual-dispatch-limit

C#: Guard against virtual dispatch branching too much.

Author: hvitved

csharp/ql/src/semmle/code/csharp/dispatch/Dispatch.qll

@@ -508,7 +508,7 @@ private module Internal {
     override RuntimeCallable getADynamicTarget() {
       result = getAViableInherited()
       or
-      result = getAViableOverrider()
+      result = getAViableOverrider() and strictcount(getAViableOverrider()) < 1000
       or
       // Simple case: target method cannot be overridden
       result = getAStaticTarget() and