Allow to edit date of birth to a later date than date of admission

[nus-se-script]

original db - 2019-01-01 original da - 2019-02-02

edit 1 db/2019-03-03 allows user to change the db to a later date than the da

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_{[original: nus-cs2103-AY2324S1/pe-interim#3309] [original labels: type.FunctionalityBug severity.Medium]}

[Blizzeracz]

Team's Response

Duplicated. Edit command does not check for the DOB < DOA constraint, which was an oversight on our part.

Duplicate status (if any):

Duplicate of #5843