add new tests for buyers login

[EddyShimwa]

This pull request introduces improved two-factor authentication (2FA) for vendor accounts, enhancing login security and protecting against unauthorized access.

✅ Used MailGUN instead of node Mailer to reduce the time it takes to send the code to the Email from >45 seconds to <10 seconds

Implemented Features:

• 2FA Setup API Endpoint: Vendors can enable 2FA through a dedicated API endpoint.
• Email verification (basic implementation)
• 2FA Verification during Login: Login attempts require a valid 2FA code in addition to the password.
• Error Handling and Responses: Clear and informative error messages are provided for various scenarios.

Definition of Done:

• All acceptance criteria are met.
• Unit tests cover all functionalities.
• Add the tests to check when the user is a Buyer to not enable 2fa authentincation
• Code adheres to coding standards and best practices.
• API documentation is included.
  Additional Notes:

Related Issues:
#31

To use the Code

• Clone this repository:
  git clone https://github.com/atlp-rwanda/dynamites-ecomm-be.git
• Run:
  npm run dev
• Test-covarage:
  npm run test:ci

##Screenshots

[bertrandshema]

It is all good for me

[Habinezajanvier]

👍

[bertrandshema]

Good now

[wayneleon1]

That looks fine for me