fix typo in sis documentation
fix typo in sis documentation

fixes SIS-2807

test plan
it should say 'section' not 'account'

Change-Id: Ica1ec5a3a519a2257ea5803fe933506874e8fa37
Reviewed-on: https://gerrit.instructure.com/115488
Reviewed-by: Rob Orton <7e09c9d3e96378bf549fc283fd6e1e5b7014cc33@instructure.com>
Product-Review: Rob Orton <7e09c9d3e96378bf549fc283fd6e1e5b7014cc33@instructure.com>
QA-Review: Rob Orton <7e09c9d3e96378bf549fc283fd6e1e5b7014cc33@instructure.com>
Tested-by: Jenkins

venturehive/canvas-lms,instructure/canvas-lms,venturehive/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,venturehive/canvas-lms,sfu/canvas-lms,venturehive/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,instructure/canvas-lms