set student progression pagination container

test plan:
 - have a course with more than 50 students and only one module
 - go to /courses/X/modules/progressions in a full-screen
   browser window (the key here is that the page needs to fit
   in the window vertically so there is no scrollbar attached
   to the window)
 - scroll down through the list of students on the right side
 - the second page of students should load
 - also, test viewing this page as a student (you should still
   see your own progression on the left)

I suggest testing in Firefox because Chrome sends a Window
scroll event even when there is nowhere to scroll

fixes CNVS-14255

Change-Id: Ib12b44e9d047b35193913be5e91e1f9dee74fa43
Reviewed-on: https://gerrit.instructure.com/38749
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Clay Diffrient <cdiffrient@instructure.com>
QA-Review: Clare Strong <clare@instructure.com>
Product-Review: Jeremy Stanley <jeremy@instructure.com>