[Tests] Write automated Postman tests for the API

[aniri]

Test the most important API calls:

• get apps ➡️ check that all info for apps are retrieved
• add app ➡️ check that all info for the app are saved
• edit app ➡️ check that all info for the app are edited

Useful links:

• https://blog.getpostman.com/2014/03/07/writing-automated-tests-for-apis-using-postman/
• https://blog.getpostman.com/2014/04/17/how-to-write-automated-tests-for-apis-with-postman-part-2/
• https://blog.getpostman.com/2014/05/09/writing-automated-tests-with-postman-part-3/

Let us know if you would like to use a different testing framework 😄

Best practices for reporting new issues:

• add the [Bug] prefix in the title
• clearly mention the steps to reproduce the bug and the expected behaviour

[jonattfin]

@aniri I will write tests for the specified methods.

[shyambh]

Hi @aniri ! I would like to work on this. Can you please assign this to me?