Error message not appropriate for import input

[nus-se-bot]

Steps to reproduce
import random.csv

Expected result
Error message stating that the file does not exist.

Actual result
Error message stating that the file cannot be read (but it doesn't exist in the first place)

Screenshots

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_{[original: nus-cs2103-AY2122S1/pe-interim#5778] [original labels: severity.Low type.FeatureFlaw]}

[jonas-chow]

Team's Response

The file not existing is a subset of failing to read from the file.

i.e. I failed to read from the file because the file does not exist

Duplicate status (if any):

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