[PLT-1684] Vb/step reasoning ontology plt 1684

[vbrodsky]

Description

Story: https://labelbox.atlassian.net/browse/PLT-1684

This implements sdk support for StepReasoning ontology feature

Notes:

• requirements: here and here
• this feature in a number of respects is different from all other Tools we have implemented so far:
  • it does not support classifications
  • it allows for very little customization
  • it has a definition field, something other Tool(s) do not
  • so I have made it a separate class
• from the implementation perspective, ontology tools / classifications are dataclasses, not pydantic models. They require a little more coding and also we are doing things 'somewhat differently' as a result. I will add a story to convert these classes pydantic models for consistency (and should result in removing some code)

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Document change (fix typo or modifying any markdown files, code comments or anything in the examples folder only)

All Submissions

• Have you followed the guidelines in our Contributing document?
• Have you provided a description?
• Are your changes properly formatted?

New Feature Submissions

• Does your submission pass tests?
• Have you added thorough tests for your new feature?
• Have you commented your code, particularly in hard-to-understand areas?
• Have you added a Docstring?

Changes to Core Features

• Have you written new tests for your core changes, as applicable?
• Have you successfully run tests with your changes locally?
• Have you updated any code comments, as applicable?