converts add_group_category js_block into js_bundle

test plan:
* regression test add group category results

Change-Id: I1933791d655eadfdb59cb50c5f7111b10e79cd8d
Reviewed-on: https://gerrit.instructure.com/29141
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Jon Jensen <jon@instructure.com>
Product-Review: Marc LeGendre <marc@instructure.com>
QA-Review: Marc LeGendre <marc@instructure.com>