tasks.register_model function incorrectly allows users to import Python models to SAS Viya 4 #137

Describe the issue
As seen in issue #136, when attempting to import a Python model with register_model() to SAS Viya 4, the normal process for SAS Viya 3.5 is used which produces a DS2 wrapped version of the Python model. This approach is not valid in SAS Viya 4, as SAS Model Manager creates the DS2 wrapper when publishing or scoring the model.

To Reproduce
Follow any of the example scripts that use register_model() to import a Python model.

Expected behavior
python-sasctl should be checking against the version of SAS Viya that register_model is attempting to import to. If a Python model is detected and SAS Viya 4 is detected, an error should be produced stating that this function cannot import models into SAS Viya 4 successfully.

Version
1.7.3