fix page error on discussion announcement, fixes #8292
fix page error on discussion announcement, fixes #8292

test plan:
* create a new announcement that is from an external feed
* go to look at it, make sure there is not a page error

Change-Id: I8d641f076914c945a0ea022128a9e9976090b9a4
Reviewed-on: https://gerrit.instructure.com/10270
Tested-by: Jenkins <d95b56ce41a2e1ac4cecdd398defd7414407cc08@instructure.com>
Reviewed-by: Simon Williams <088e16a1019277b15d58faf0541e11910eb756f6@instructure.com>

rup/Tarrax,va7map/canvas-lms,merichar/canvas-lms,landonwilkins/canvas-lms,roxolan/canvas-lms,venturehive/canvas-lms,HotChalk/canvas-lms,parbros/red-innovadores-lms,usmschuck/canvas,sfu/canvas-lms,landonwilkins/canvas-lms,djbender/canvas-lms,juoni/canvas-lms,sfu/canvas-lms,redconfetti/canvas-lms,shidao-fm/canvas-lms,tgroshon/canvas-lms,arrivu/jigsaw-lms,sli7246/canvas_branch,efrj/canvas-lms,wimemx/Canvas,parbros/red-innovadores-lms,nditech/red-innovadores-lms,sli7246/canvas_branch,sfu/canvas-lms,utkarshx/canvas-lms,whalejasmine/canvas-lms,nditech/red-innovadores-lms,usmschuck/canvas,leftplusrightllc/canvas-lms,samuels410/greatlakes-lms,shidao-fm/canvas-lms,nditech/red-innovadores-lms,sfu/canvas-lms,arrivu/hoodemo,fronteerio/canvas-lms,fronteerio/canvas-lms,leftplusrightllc/canvas-lms,sfu/canvas-lms,arrivu/jigsaw-lms,juoni/canvas-lms,redconfetti/canvas-lms,juoni/canvas-lms,ankithbti/canvas_lms,sfu/canvas-lms,venturehive/canvas-lms,Jyaasa/canvas-lms,wimemx/Canvas,va7map/canvas-lms,grahamb/canvas-lms,wrdsb/canvas-lms,leftplusrightllc/canvas-lms,wrdsb/canvas-lms,SwinburneOnline/canvas-lms,Unow/canvas-lms,sdeleon28/canvas-lms,arrivu/qibla-ecampus,sdeleon28/canvas-lms,HotChalk/canvas-lms,arrivu/qibla-ecampus,loganrun/pincan,SwinburneOnline/canvas-lms,Jyaasa/canvas-lms,utkarshx/canvas-lms,leftplusrightllc/canvas-lms,grahamb/canvas-lms,skmezanul/canvas-lms,jay3126/canvas-lms,ShreniiNepal/shrenii_lmp,va7map/canvas-lms,greyhwndz/canvas-lms,em2/canvas-lms,greyhwndz/canvas-lms,jay3126/canvas-lms,Unow/ins,shidao-fm/canvas-lms,jay3126/canvas-lms,arrivu/arrivu-lms,ankithbti/canvas_lms,jay3126/canvas-lms,venturehive/canvas-lms,loganrun/pincan,samuels410/greatlakes-lms,landonwilkins/canvas-lms,djbender/canvas-lms,skmezanul/canvas-lms,skmezanul/canvas-lms,efrj/canvas-lms,antoniuslin/canvas-lms,em2/canvas-lms,whalejasmine/canvas-lms,loganrun/pincan,wye0220/shindig-canvas,utkarshx/canvas-lms,grahamb/canvas-lms,sli7246/canvas_branch,Rvor/canvas-lms,ankithbti/canvas_lms,roxolan/canvas-lms,SwinburneOnline/canvas-lms,arrivu/hoodemo,efrj/canvas-lms,arrivu/arrivu-lms,landonwilkins/canvas-lms,merichar/canvas-lms,arrivu/hoodemo,samuels410/greatlakes-lms,shidao-fm/canvas-lms,whalejasmine/canvas-lms,HotChalk/canvas-lms,tgroshon/canvas-lms,tgroshon/canvas-lms,Unow/ins,Rvor/canvas-lms,utkarshx/canvas-lms,greyhwndz/canvas-lms,wrdsb/canvas-lms,nditech/red-innovadores-lms,Unow/ins,djbender/canvas-lms,wrdsb/canvas-lms,ShreniiNepal/shrenii_lmp,usmschuck/canvas,roxolan/canvas-lms,Rvor/canvas-lms,fronteerio/canvas-lms,Rvor/canvas-lms,efrj/canvas-lms,arrivu/arrivu-lms,SwinburneOnline/canvas-lms,merichar/canvas-lms,grahamb/canvas-lms,tgroshon/canvas-lms,juoni/canvas-lms,va7map/canvas-lms,antoniuslin/canvas-lms,HotChalk/canvas-lms,arrivu/jigsaw-lms,rup/Tarrax,djbender/canvas-lms,antoniuslin/canvas-lms,Jyaasa/canvas-lms,kyroskoh/canvas-lms,skmezanul/canvas-lms,wye0220/shindig-canvas,parbros/red-innovadores-lms,samuels410/greatlakes-lms,ShreniiNepal/shrenii_lmp,venturehive/canvas-lms,whalejasmine/canvas-lms,greyhwndz/canvas-lms,sdeleon28/canvas-lms,arrivu/qibla-ecampus,wye0220/shindig-canvas,wimemx/Canvas,kyroskoh/canvas-lms,Unow/canvas-lms,antoniuslin/canvas-lms,em2/canvas-lms,Jyaasa/canvas-lms,usmschuck/canvas,grahamb/canvas-lms,roxolan/canvas-lms,ShreniiNepal/shrenii_lmp,sfu/canvas-lms,kyroskoh/canvas-lms,Unow/canvas-lms,redconfetti/canvas-lms,redconfetti/canvas-lms,sdeleon28/canvas-lms,fronteerio/canvas-lms,kyroskoh/canvas-lms,rup/Tarrax