Move all categorize blockhash code to one "CategorizeBlockHash".

Author: jan-elastic

x-pack/plugin/esql/compute/src/main/java/org/elasticsearch/compute/aggregation/blockhash/AbstractCategorizeBlockHash.java

@@ -180,9 +180,7 @@ public static BlockHash buildCategorizeBlockHash(
             throw new IllegalArgumentException("only a single CATEGORIZE group can used");
         }
 
-        return aggregatorMode.isInputPartial()
-            ? new CategorizedIntermediateBlockHash(groups.get(0).channel, blockFactory, aggregatorMode.isOutputPartial())
-            : new CategorizeRawBlockHash(groups.get(0).channel, blockFactory, aggregatorMode.isOutputPartial(), analysisRegistry);
+        return new CategorizeBlockHash(blockFactory, groups.get(0).channel, aggregatorMode, analysisRegistry);
     }
 
     /**