Fix sequence widget
Fix sequence widget

Summary:
Before, the sequence widget was broken — although you could enter in
multiple steps, only the first would show up even when you inputted the
correct answer.

This issue was partly created in D14568 and because Group widgets never
seemed to care about a `onInteractWithWidget` prop in the first place.

This diff passes the `onInteractWithWidget` into the Renderer instead
of the Group widgets and extracts the step from the ID of the Group
widget that was interacted with.

Test Plan: Visit [this Perseus link](http://localhost:9000/article.html#content=%5B%7B%22content%22%3A%22Hi%20I%27m%20a%20particle%21%5Cn%5Cn%5B%5B%E2%98%83%20sequence%201%5D%5D%5Cn%5Cn%22%2C%22images%22%3A%7B%7D%2C%22widgets%22%3A%7B%22sequence%201%22%3A%7B%22type%22%3A%22sequence%22%2C%22alignment%22%3A%22default%22%2C%22graded%22%3Atrue%2C%22options%22%3A%7B%22json%22%3A%5B%7B%22content%22%3A%22%5B%5B%E2%98%83%20categorizer%201%5D%5D%5Cn%5Cn%22%2C%22images%22%3A%7B%7D%2C%22widgets%22%3A%7B%22categorizer%201%22%3A%7B%22type%22%3A%22categorizer%22%2C%22alignment%22%3A%22default%22%2C%22graded%22%3Atrue%2C%22options%22%3A%7B%22items%22%3A%5B%221%22%2C%222%22%5D%2C%22categories%22%3A%5B%22Correct%22%2C%22Incorrect%22%5D%2C%22values%22%3A%5B0%2C0%5D%2C%22randomizeItems%22%3Afalse%7D%2C%22version%22%3A%7B%22major%22%3A0%2C%22minor%22%3A0%7D%7D%7D%7D%2C%7B%22content%22%3A%22%5B%5B%E2%98%83%20radio%201%5D%5D%5Cn%5Cn%22%2C%22images%22%3A%7B%7D%2C%22widgets%22%3A%7B%22radio%201%22%3A%7B%22type%22%3A%22radio%22%2C%22alignment%22%3A%22default%22%2C%22graded%22%3Atrue%2C%22options%22%3A%7B%22choices%22%3A%5B%7B%22correct%22%3Afalse%2C%22content%22%3A%22This%20is%20wrong%22%7D%2C%7B%22correct%22%3Atrue%2C%22content%22%3A%22This%20is%20right%22%7D%5D%2C%22randomize%22%3Afalse%2C%22multipleSelect%22%3Afalse%2C%22displayCount%22%3Anull%2C%22hasNoneOfTheAbove%22%3Afalse%2C%22onePerLine%22%3Atrue%2C%22deselectEnabled%22%3Afalse%7D%2C%22version%22%3A%7B%22major%22%3A1%2C%22minor%22%3A0%7D%7D%7D%7D%2C%7B%22content%22%3A%22Done%21%22%2C%22images%22%3A%7B%7D%2C%22widgets%22%3A%7B%7D%7D%5D%7D%2C%22version%22%3A%7B%22major%22%3A0%2C%22minor%22%3A0%7D%7D%7D%7D%5D) and verify that the Sequence widget works.

Reviewers: aria

Subscribers: kevindangoor

Differential Revision: https://phabricator.khanacademy.org/D20116

ariabuckles/perseus,ariabuckles/perseus,alexristich/perseus,ariabuckles/perseus,learningequality/perseus,alexristich/perseus,sachgits/perseus,learningequality/perseus,iamchenxin/perseus,ariabuckles/perseus,sachgits/perseus,iamchenxin/perseus