update ar translation
update ar translation

Change-Id: Icf047d26364008499ef9a02b84c06d3c4742d80f

djbender/canvas-lms,sfu/canvas-lms,SwinburneOnline/canvas-lms,venturehive/canvas-lms,matematikk-mooc/canvas-lms,instructure/canvas-lms,matematikk-mooc/canvas-lms,instructure/canvas-lms,SwinburneOnline/canvas-lms,venturehive/canvas-lms,SwinburneOnline/canvas-lms,matematikk-mooc/canvas-lms,grahamb/canvas-lms,sfu/canvas-lms,grahamb/canvas-lms,grahamb/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,grahamb/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,venturehive/canvas-lms,instructure/canvas-lms,matematikk-mooc/canvas-lms,sfu/canvas-lms,grahamb/canvas-lms,SwinburneOnline/canvas-lms,instructure/canvas-lms,venturehive/canvas-lms,sfu/canvas-lms