feat(test_utils): Add custom-headers and custom delay support to rustman

[pixincreate]

Type of Change

• New feature
• Documentation
• CI/CD

Description

Closes #2646
This PR as usual, narrows the main aim of rustman by making specific to Hyperswitch. With this, you should now be able to:

• Set delay between each request sent as per your own wish while default being 7 milliseconds
• Pass in custom-headers of your wish in run time

How custom-headers works

Custom headers inject the headers that you pass in command line into the event.prerequest.js file and sets a flag to true. After the collection is run, it checks the flag and depending on that, it will git checkout HEAD -- <collection_name>/event.prerequest.js to restore the file to same as before.
We can also pass -e environment.json where you pass in custom headers but that requires some significant changes to be done to the collections to support that.

Motivation and Context

This will allow us to pass different headers in run-time to test new things and also allow you to set delay of your wish. You can now set the delay to 100000000000 and wait for ages to run a single test :D

How did you test it?

Command used: (Custom headers taken from #2116)
Delay set to 0.5 seconds

cargo run --bin test_utils -- --base_url=http://127.0.0.1:8080 --admin_api_key=test_admin --connector_name=stripe --folder "QuickStart" --header "payment_confirm_source:merchant_server" --header "another_header_key:and_its_value" --delay_request 4294967295

In run-time, we can see the custom-headers being injected here:

Value being stored in DB:

Ran Stripe Collection:

Checklist

• I formatted the code cargo +nightly fmt --all
• I addressed lints thrown by cargo clippy
• I reviewed the submitted code