feat: Sample app for big payload application

[kapishupadhyay22]

here is a nodejs sample application for testing big payload feature in integration testing for keploy.

[keploy]

To generate Unit Tests for this PR, please click here.

[Sarthak160]

@kapishupadhyay22 We can add a better endpoint which will return an array of json objects and the payload size can be adjusted according to the size of the array.

[kapishupadhyay22]

@kapishupadhyay22 We can add a better endpoint which will return an array of json objects and the payload size can be adjusted according to the size of the array.

I have implemented it