chore: Remove more redundant code in utils/core (#25986)

tests/integration_tests/utils_tests.py

@@ -59,7 +59,6 @@ from superset.utils.core import (
     get_stacktrace,
     json_int_dttm_ser,
     json_iso_dttm_ser,
-    JSONEncodedDict,
     merge_extra_filters,
     merge_extra_form_data,
     merge_request_params,
@@ -583,15 +582,6 @@ class TestUtils(SupersetTestCase):
             "-16 days, 4:03:00",
         )
 
-    def test_json_encoded_obj(self):
-        obj = {"a": 5, "b": ["a", "g", 5]}
-        val = '{"a": 5, "b": ["a", "g", 5]}'
-        jsonObj = JSONEncodedDict()
-        resp = jsonObj.process_bind_param(obj, "dialect")
-        self.assertIn('"a": 5', resp)
-        self.assertIn('"b": ["a", "g", 5]', resp)
-        self.assertEqual(jsonObj.process_result_value(val, "dialect"), obj)
-
     def test_validate_json(self):
         valid = '{"a": 5, "b": [1, 5, ["g", "h"]]}'
         self.assertIsNone(validate_json(valid))