Fix codeowner specification for the Brazilian Portuguese translation

Author: spier

.github/CODEOWNERS

@@ -14,8 +14,8 @@
 /book/ja/           @yuhattor
 /translation/zh/    @WillemJiang
 /book/zh/           @WillemJiang
-/translation/pt/    @jrcosta @zilio
-/book/pt/           @jrcosta @zilio
+/translation/pt-br/    @jrcosta @zilio
+/book/pt-br/           @jrcosta @zilio
 /pattern-categorization/pt-br/    @jrcosta @zilio
 /translation/gl/    @psanxiao
 /book/gl/           @psanxiao