update pt-BR translation
update pt-BR translation

Change-Id: I91444a764375456603dc584454bb9c652eb3a036
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/253314
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