add command able to add 2 different persons with 2 different names but the same email

[Zack-Tay]

Steps to reproduce

Running commands:

1. add n/John Wong t/friend e/Wong@example.com a/Newgate Prison p/1234567 t/criminal
2. add n/Joe Wong t/friend e/Wong@example.com a/Newgate Prison p/1234567 t/criminal

Expected

By right, in a real world context, system tells user that there is already a contact with the same email that exist.

Actual

Application here accepts having 2 persons with different name but same email. Email can be said to identify an individual as well.

Screenshots

[nus-se-script]

Team's Response

Two people can Absolutely use the same email. For example.

1. an elderly couple not familiar with emails.
2. Me and my friend sharing the same steam account that we create using an email that both of us own.
3. 2+ external service providers(from the same company) for your event that leaves same company email as their official contact method.

   Items for the Tester to Verify

   :question: Issue response

Team chose [response.Rejected]

• [x] I disagree

Reason for disagreement: This bug represents a valid concern with the application. Supposed by accident that 2 different persons are added to the system with the same email address (either because the emails are too similar such that the user enters wrongly or any other plausible reasons), this could create bookkeeping information issues as well.

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