Explicitly set correctness in radio transform.
Explicitly set correctness in radio transform.

Summary:
This fixes https://app.asana.com/0/265849773833386/458274487120641
(rationales sometimes incorrectly being shown as correct).

This also removes some React warnings when in development mode.

Test Plan:
 - Ran `make watch`
 - In Khan Academy, went to http://localhost:8080/math/ap-calculus-ab/ab-antiderivatives-ftc/ab-u-substitution/e/u-substitution-defining-u with the content_library_rationales and final_multiple_choice_styles gandalf bridges enabled
 - Tried 16 problems, and did not get any JS dialogs or answers with
   more than one solution marked as correct.

Reviewers: emily

Reviewed By: emily

Spies: tom, jared

Differential Revision: https://phabricator.khanacademy.org/D40531

ariabuckles/perseus,learningequality/perseus,ariabuckles/perseus,ariabuckles/perseus,ariabuckles/perseus,learningequality/perseus