View command does not handle faulty inputs

[nus-pe-bot]

When view is entered with:

1. no additional parameter, view
2. non-integer parameter, view abc

No alert message is displayed.

I would expect a error message stating that an index is required. For example, something similar to the below delete command error message.

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_{[original: nus-cs2103-AY2223S2/pe-interim#1562] [original labels: type.FunctionalityBug severity.High]}

[Gibson0918]

Team's Response

Severity should be medium instead since it does not affect the functionality of the view function, but lowers the user's experience of viewing contact details.

Duplicate status (if any):

Duplicate of #2777