[Expenditure: Add] Incorrect Error message

[nus-se-script]

When entering a negative value into the amount, the error message different from the expected error:

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_{[original: nus-cs2113-AY2324S2/pe-interim#196] [original labels: severity.Low type.FeatureFlaw]}

[Heart-of-N1]

Team's Response

We cannot reproduce this bug.

In addition, it is an unknown command because there exists an additional '/' before date/.

Duplicate status (if any):

Duplicate of #233