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

Change-Id: I0489d1e2d745caf52d36d01aeb3693a0608ed3fd
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/228165
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>

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