Older examples needs to be updated for JSONFiles API changes

Describe the issue
This example has some API calls that don't work with the updated version of sasctl - changes to JSONFiles:
https://github.com/sassoftware/python-sasctl/blob/master/examples/pzmmCompleteModelExampleMLFlowSklearn.ipynb

For example, writeModelPropertiesJSON is now write_model_properties_json and has many changes in the parameters.

Other examples:
writeFileMetadataJSON
writeVarJSON

I checked other examples and it seems any of them 6 months or older are now out of date with the newer sasctl API.

To Reproduce
Run this command using latest sasctl

J.writeVarJSON(inputsDict, isInput=True, jPath=zipFolder)

and you will get things like

AttributeError: 'JSONFiles' object has no attribute 'writeVarJSON'. Did you mean: 'write_var_json'?

Version
The SHA is 729e72c8785065109ccfd1ffdb9816d4bf1dce55

从 examples/pzmmCompleteModelExampleMLFlowSklearn.ipynb 开始，将其中的 JSONFiles 调用与当前的 sasctl API 进行比较。在其他示例中搜索 writeModelPropertiesJSON、writeFileMetadataJSON 和 writeVarJSON，然后更新已过时的调用和参数。完成的标准是，较旧的示例能够使用最新的 sasctl 运行，且不会出现所报告的 AttributeError。