converts calendars/_wizard_box js_block into js_bundle

test plan:
* regression on calendars wizard box

Change-Id: Ifec88952daf715e1793f4165c604e77dd5e3e8a2
Reviewed-on: https://gerrit.instructure.com/29168
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Stanley Stuart <stanley@instructure.com>
QA-Review: Matt Fairbourn <mfairbourn@instructure.com>
Product-Review: Landon Wilkins <lwilkins@instructure.com>