[BUG] Add request validators to all the routes and change the ENDPOINT.md accordingly

[ighoshsubho]

• v2 of Fintech API repo needs to have validations to all the routes and due to them the endpoints become POST request instead of GET
• After adding request validations to all the routes, test it with the /docs route
• Add the request and responses accordingly in the ENDPOINTS.md

[github-actions[bot]]

👋 @ighoshsubho

Thank you for raising an issue. We will investigate into the matter and get back to you as soon as possible.

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[Codeansh]

Please assign this issue to me, I'll do this.

[DEEKSHACodeaim]

@ighoshsubho, I would like to take this issue , please assign it to me if not yet fixed.

[Codeansh]

I am working on it.

[pooranjoyb]

@ighoshsubho Can you assign me this issue as there hasn't been any activity from last 2 weeks?

[Codeansh]

Actually, I was busy, but now am available and I'll fix it as soon as possible.