fix: refactor product categories endpoint

[Muhammad235]

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Description

​This PR refactors product categories endpoint to match the c# doc

Related Issue (Link to Github issue)

​issue here

Motivation and Context

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How Has This Been Tested?

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Screenshots (if appropriate - Postman, etc):

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change) ​

  Checklist:

• [x] My code follows the code style of this project.
• [x] My change requires a change to the documentation.
• [x] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [x] I have added tests to cover my changes.
• [x] All new and existing tests passed.