Add command/edit command allow same telegram and github username

[nus-se-bot]

github and telegram usernames and emails should not have duplicates which were allowed as shown below. Michael Tay and John Doe are different people yet share the same telegram, github usernames as well as email addresses.

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_{[original: nus-cs2103-AY2122S2/pe-interim#505] [original labels: type.FunctionalityBug severity.Medium]}

[jaysmyname]

Team's Response

Accepted, but should be of severity Low since it is not stated in the user guide that Telegram, Github and emails are checked for duplicate entries, but names are.

Duplicate status (if any):

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