Remove @UpdateForV9 annotation (#125024)

* Delete libs/core/src/main/java/org/elasticsearch/core/UpdateForV9.java

* Remove UpdateForV9 annotation in ConsumeProcessor.java

Author: arpadkiraly

libs/core/src/main/java/org/elasticsearch/core/UpdateForV9.java

@@ -42,7 +42,6 @@ public Set<String> getSupportedAnnotationTypes() {
             "org.elasticsearch.xpack.esql.expression.function.MapParam",
             "org.elasticsearch.rest.ServerlessScope",
             "org.elasticsearch.xcontent.ParserConstructor",
-            "org.elasticsearch.core.UpdateForV9",
             Fixed.class.getName()
         );
     }