Overzealous input validation for phone number

[nus-pe-bot]

Explanation: Program does not allow for phone number with dashes. It is better to warn rather than block such inputs.

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_{[original: nus-cs2103-AY2324S2/pe-interim#5300] [original labels: severity.Low type.FeatureFlaw]}

[brennalaurentan]

Team's Response

It has already been stated in the user guide that only numeric inputs are accepted as a valid parameter for the phone number field.

Additionally, the screenshot provided does not reflect the bug brought up in text, in the bug report.

Duplicate status (if any):

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