Revert "enhance: Convert json_cast_type to DataType (#2690)" (#2692)

This reverts commit b2bca89.

Signed-off-by: sunby <[email protected]>

Author: sunby

pymilvus/client/grpc_handler.py

@@ -9,7 +9,6 @@
 import grpc
 from grpc._cython import cygrpc
 
-from pymilvus.client.types import DataType
 from pymilvus.decorators import ignore_unimplemented, retry_on_rpc_failure, upgrade_reminder
 from pymilvus.exceptions import (
     AmbiguousIndexName,
@@ -1145,8 +1144,6 @@ def describe_index(
             info_dict = {kv.key: kv.value for kv in response.index_descriptions[0].params}
             info_dict["field_name"] = response.index_descriptions[0].field_name
             info_dict["index_name"] = response.index_descriptions[0].index_name
-            if info_dict.get("json_cast_type"):
-                info_dict["json_cast_type"] = DataType(int(info_dict["json_cast_type"]))
             if info_dict.get("params"):
                 info_dict["params"] = json.loads(info_dict["params"])
             info_dict["total_rows"] = response.index_descriptions[0].total_rows