Allow Filtering by postman collection

[MaggieKimani1]

This PR:

• Adds a --filterByCollection command option to the transform command
• Updates the OpenApiFilterService with logic for slicing OpenAPI documents based on postman collections.
• Adds tests to validate for filtering by postman collections

Testing Instructions:

• To use the new command option, append the --filterByCollection "file.json" parameter to the transform command
  E.g:
  transform --input C:\Users\Downloads\response.yaml --output C:\Users\source\repos\response2.yml --format yaml --version OpenApi3_0 --filterByCollection C:\Users\Downloads\Graph-Collection-43402ca3-f018-7c9b-2315-f176d9b171a3.postman_collection.json

Fixes #650