Different exception message for similar errors for addsubtrip

[nus-se-script]

Adding subtrip with starting date out of range throws "Failure to parse dates ..." while adding subtrip with ending date out of range throws "... not within range ..."

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_{[original: nus-cs2113-AY2324S2/pe-interim#2416] [original labels: type.FeatureFlaw severity.VeryLow]}

[azamanis]

Team's Response

The problem in the first command is a typo in the second date: "2024-0421"

Duplicate status (if any):

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