[UI] Visual bug after photo command used with a high-resolution image

[nus-se-bot]

Describe the bug
#Using the photo command to add a photo of high resolution (5100 x 3400) to a Person causes visual bugs to appear in the Person list, and unrelated Person cards.

To Reproduce
Steps to reproduce the behavior:

1. Use photo command to add a photo of high resolution to a Person

Expected behavior

• The person card involved in the add command displays correctly
• The other Person cards not involved in the add command display correctly
• The other Person cards not involved in the add command remain selectable using clicks

Screenshots

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Reported by: @shaungohsc
Severity: Low

_{[original: nus-cs2103-AY1819S2/pe-dry-run#534]}

[yinya998]

The cause of this problem is still not clear.
I have tried adding an image of 40mb and it works fine. So the system should be able to work with file that are smaller than 40mb. I put a size check in case the problem is caused by file size.