update ko translation
update ko translation

Change-Id: Iaefd8ea26449942f4e27359f8c23551194ebe933
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/287392
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>

sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms