update nb-x-k12 translation
update nb-x-k12 translation

Change-Id: Ia3dbb645c420b3c8e403e0b51670fb670fcd0f6a
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/268350
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>

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