With the latest version of the desktop app (1.16.17), you can configure post-request scripts at the flow level! Flow-level post-request scripts run code after every request in an API test. They can be useful if, for example, you want every step to perform a particular cleanup action to leave the system under test ready for the next request.
To add a flow-level script to an API test, open the API Test Editor and use the pencil icon in the flow title card to bring up the flow properties modal.
In the modal head over to Post-request tab and edit your script code as needed. Close the modal using the X icon when you are happy with the script.
For more information on how you can add custom scripts to your API tests, check out the guide.