Attempting to serialize bytes type causes error

[ava-harris]

PySDK Version

• PySDK V2 (2.x)
• PySDK V3 (3.x)

Describe the bug
When attempting to call the invoke function with a bytes object in the body, it throws an error during serialization. This is because bytes are not treated as a primitive.

sagemaker-python-sdk/sagemaker-core/src/sagemaker/core/utils/utils.py

Lines 523 to 527 in 302b973

	elif is_not_primitive(value):
	# if the value is a dict, use _serialize_shape() to serialize it recursively
	return _serialize_shape(value)
	else:
	return value

sagemaker-python-sdk/sagemaker-core/src/sagemaker/core/utils/utils.py

Lines 275 to 276 in 302b973

	def is_not_primitive(obj):
	return not isinstance(obj, (int, float, str, bool, datetime.datetime))

To reproduce

from sagemaker.core.utils.utils import serialize
serialize({"body": b'1'})

Expected behavior

{'body': b'1'}

Screenshots or logs
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System information
A description of your system. Please provide:

• SageMaker Python SDK version: 3.6.0
• Framework name (eg. PyTorch) or algorithm (eg. KMeans): N/A
• Framework version: N/A
• Python version: 3.12.9
• CPU or GPU: N/A
• Custom Docker image (Y/N): N

Additional context
Add any other context about the problem here.