Wrong error message for add goods

[nus-pe-bot]

Should show that the date itself is invalid (ie month cannot be 13) not that the format is invalid

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_{[original: nus-cs2103-AY2425S1/pe-interim#2843] [original labels: type.FeatureFlaw severity.Low]}

[yanhwee]

Team's Response

The invalidity of the date format implies that the date itself is invalid. The error message correctly specifies that the date should be between 1-12 (MM), as per common date formats.

However, I suppose that it can be clearer.

Duplicate status (if any):

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