Subclasses of dict (like `Label`) do not work with `camel_case=False`

System information

• Python Version: 3.8.13
• SDK Version: 4.11.3

Describe the bug
Argument camel_case=False for multiple Cognite classes that subclass dict doesn't work because of declared properties with camelCase names, e.g. Label and ExtractionPipelineContact.

To Reproduce
Runnable code reproducing the error.

>>> from cognite.client.data_classes import Label
>>> ll = Label(external_id="what-the-fox")
>>> ll.dump(camel_case=False)
{'externalId': 'what-the-fox'}  # not snake cased
>>> ll.dump(camel_case=True)
{'externalId': 'what-the-fox'}

Or (notice sendNotification always in camel case):

>>> from cognite.client.data_classes import ExtractionPipelineContact
>>> epc = ExtractionPipelineContact(name="Fox", email="NA", role="Singer", send_notification=False)
>>> epc.dump(camel_case=False)
{'name': 'Fox', 'email': 'NA', 'role': 'Singer', 'sendNotification': False}
>>> epc.dump(camel_case=True)
{'name': 'Fox', 'email': 'NA', 'role': 'Singer', 'sendNotification': False}

Start with the dump behavior of the Label and ExtractionPipelineContact examples, then trace how dict subclasses handle the camel_case argument. Run the provided reproducer and add regression coverage showing that camel_case=False produces snake_case keys while camel_case=True preserves camelCase output.