Ruby: Fix performance of Filter.getAnAction

Only look at the current class and the immediate superclass.
This will miss some edge cases but is much faster.

Author: hmac

ruby/ql/lib/codeql/ruby/frameworks/actioncontroller/Filters.qll

@@ -65,13 +65,14 @@ module Filters {
         not exists(this.getOnlyArgument()) and
         forall(string except | except = this.getExceptArgument() | result.getName() != except)
       ) and
+      // This is a simple heuristic and will miss some cases.
       (
-        result = this.getExpr().getEnclosingModule().getAMethod()
+        // The action is in the same class as this call
+        result = lookupMethod(this.getExpr().getEnclosingModule().getModule(), _)
         or
-        exists(ModuleBase m |
-          m.getModule() = this.getExpr().getEnclosingModule().getModule().getADescendent() and
-          result = m.getAMethod()
-        )
+        // or the action is in an immediate subclass of this call
+        result.getEnclosingModule().getModule().getAnImmediateAncestor() =
+          this.getExpr().getEnclosingModule().getModule()
       )
     }