refractor: optimize readme file

[fabio-nettis]

Description

This PR optimizes the general readability of the readme file. I deleted the entities from the readme file since they are already explained inside the postman collection.

Type of change

• Refractor (non-breaking change which cleans up code)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules