Update InstUI import sources in speed_grader
Update InstUI import sources in speed_grader

Closes FOO-1803
flag = none

Even though speed_grader.js is in public/javascripts instead
of app/jsx, it still makes use of React and InstUI. No code
changes, just the imports.

Test plan:
* speedgrader still works, especially Buttons, TextAreas, Pills,
  and Tooltips.

Change-Id: I0b82e219b721fd65b64a5946c915664f83d7a78c
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/262054
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>
Reviewed-by: Ed Schiebel <0ca8a83847a5889cf05cb219c0ab09f6b646243b@instructure.com>
QA-Review: Ed Schiebel <0ca8a83847a5889cf05cb219c0ab09f6b646243b@instructure.com>
Product-Review: Charley Kline <05950d7e90ba5e3da323378368c22b3ffaaf6647@instructure.com>

instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms