[DeadCode] Keep empty __construct() in anonymous class that extends parent on RemoveEmptyClassMethodRector

[TomasVotruba]

An anonymous class that extends a parent often uses an empty __construct() on purpose - to neutralize the parent constructor. Removing it changes behavior of the stub/decorator.

Now kept:

 function createStub()
 {
     return new class extends ParentWithoutConstructor {
        public function __construct()
        {
        }
     };
 }

Anonymous class without extends is still cleaned up:

 function createPlain()
 {
-    return new class {
-        public function __construct()
-        {
-        }
-    };
+    return new class {
+    };
 }