not compatible with mlflow v1.28.0

[lerit]

when run workflow:

qrun ALSTM_workflow_config_alstm_Alpha158.yaml

mlflow v1.27.0 work fine,but failed when with mlflow v1.28.0:

File "miniconda3/envs/qlibdev/lib/python3.8/site-packages/pyqlib-0.8.6.99-py3.8-linux-x86_64.egg/qlib/workflow/recorder.py", line 441, in log_params
    self.client.log_param(self.id, name, data)
  File "miniconda3/envs/qlibdev/lib/python3.8/site-packages/mlflow-1.28.0-py3.8.egg/mlflow/tracking/client.py", line 852, in log_param
    self._tracking_client.log_param(run_id, key, value)
  File "miniconda3/envs/qlibdev/lib/python3.8/site-packages/mlflow-1.28.0-py3.8.egg/mlflow/tracking/_tracking_service/client.py", line 305, in log_param
    raise MlflowException(msg, INVALID_PARAMETER_VALUE)
mlflow.exceptions.MlflowException: Param value '[{'class': 'SignalRecord', 'module_path': 'qlib.workflow.record_temp', 'kwargs': {'model': '<MODEL>', 'dataset': '<DATASET>'}}, {'class': 'SigAnaRecord', 'module_path': 'qlib.workflow.record_temp', 'kwargs': {'ana_long_short': False, 'ann_scaler': 25' had length 778, which exceeded length limit of 500

i think the new mflow feature cause this bug.mlflow limit param valu lengh to 500,by read code ,it can not be overwrite. maybe relate with this issue