update pt-BR translation
update pt-BR translation

Change-Id: I27825e1e5d0b9f0ace5822c372a5843fc0aea834
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/225085
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>

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