update pt-BR translation
update pt-BR translation

Change-Id: I76dc5f0bc312415683442a284af632c51d621ac2
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/279060
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