[POSTMAN] [BUG] Correct order of the Postman requests

[gcatanese]

The generated Postman collection presents the requests in a random order.

This PR fixes the generator to sort the requests by path to make sure Postman displays all requests for a given endpoint together.

Fixes #16982

PR checklist

• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
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  ./bin/generate-samples.sh ./bin/configs/*.yaml
  ./bin/utils/export_docs_generators.sh
  

  Commit all changed files.
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@gcatanese @wing328