ES|QL categorize tech preview -> GA (elastic#129398)

Author: jan-elastic

docs/reference/query-languages/esql/_snippets/functions/layout/categorize.md

@@ -1,2 +1,2 @@
 * [`BUCKET`](../../functions-operators/grouping-functions.md#esql-bucket)
-* [preview] [`CATEGORIZE`](../../functions-operators/grouping-functions.md#esql-categorize)
+* [`CATEGORIZE`](../../functions-operators/grouping-functions.md#esql-categorize)

docs/reference/query-languages/esql/_snippets/lists/grouping-functions.md

@@ -63,7 +63,6 @@ public class Categorize extends GroupingFunction.NonEvaluatableGroupingFunction
                 tag = "docsCategorize",
                 description = "This example categorizes server logs messages into categories and aggregates their counts. "
             ) },
-        preview = true,
         type = FunctionType.GROUPING
     )
     public Categorize(