Java: Fix test and some references.

java/ql/lib/semmle/code/java/deadcode/EntryPoints.qll

@@ -262,7 +262,7 @@ class ManagedBeanImplEntryPoint extends EntryPoint, RegisteredManagedBeanImpl {
     // Find the method that will be called for each method on each managed bean that this class
     // implements.
     this.inherits(result) and
-    result.overrides(this.getAnImplementedManagedBean().getAMethod())
+    result.overrides+(this.getAnImplementedManagedBean().getAMethod())
   }
 }
 

java/ql/lib/semmle/code/java/deadcode/StrutsEntryPoints.qll

@@ -19,7 +19,7 @@ class Struts1ActionEntryPoint extends EntryPoint, Class {
       exists(Method methodFromAction |
         methodFromAction.getDeclaringType().hasQualifiedName("org.apache.struts.action", "Action")
       |
-        result.(Method).overrides(methodFromAction)
+        result.(Method).overrides+(methodFromAction)
       )
       or
       this.getASupertype*().hasQualifiedName("org.apache.struts.actions", "DispatchAction") and