Getting "TypeError: can only join an iterable" while running "print(predictor.predict(test_data).decode("utf-8"))"

[Arpitgit11]

Link to the .ipynb file
https://github.com/aws/amazon-sagemaker-examples/blob/main/advanced_functionality/scikit_bring_your_own/scikit_bring_your_own.ipynb

Describe the bug
to me looks like predic() function is expecting a diff input

To reproduce
run all previous steps of .ipynb file till line:
print(predictor.predict(test_data).decode("utf-8"))

Logs
TypeError Traceback (most recent call last)
Cell In[89], line 2
1 import pandas as pd
----> 2 print(predictor.predict(test_data).decode("utf-8"))

File ~/anaconda3/envs/python3/lib/python3.10/site-packages/sagemaker/base_predictor.py:196, in Predictor.predict(self, data, initial_args, target_model, target_variant, inference_id, custom_attributes, component_name)
155 """Return the inference from the specified endpoint.
156
157 Args:
(...)
193 as is.
194 """
195 # [TODO]: clean up component_name in _create_request_args
--> 196 request_args = self._create_request_args(
197 data=data,
198 initial_args=initial_args,
199 target_model=target_model,
200 target_variant=target_variant,
201 inference_id=inference_id,
202 custom_attributes=custom_attributes,
203 )
205 inference_component_name = component_name or self._get_component_name()
206 if inference_component_name:

File ~/anaconda3/envs/python3/lib/python3.10/site-packages/sagemaker/base_predictor.py:256, in Predictor._create_request_args(self, data, initial_args, target_model, target_variant, inference_id, custom_attributes)
251 args["ContentType"] = jumpstart_content_type
252 else:
253 args["ContentType"] = (
254 self.content_type
255 if isinstance(self.content_type, str)
--> 256 else ", ".join(self.content_type)
257 )
259 if "Accept" not in args:
260 if isinstance(data, JumpStartSerializablePayload) and jumpstart_accept:

TypeError: can only join an iterable