Converted ImageSelector.js to Typescript

[kYpranite]

Had pre-commit error about not having a defaultProp: I added one but not sure if it is best practice or deprecated.

Also npm installed type declaration for ReactModal

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🔨 Latest commit	23631488222e3d1100760dee1307084e33de1867

[mizlan]

You can either rebase your changes atop the new master, or just redo the PR after resetting --hard to origin/master