GH-50: Fix the phone mask for Brazil

[ArtyomVancyan]

Motivation:

By @adrielschmitz's suggestion, updated the phone mask for Brazil based on the official information shared in #50 discussion.

All Submissions:

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes to Core Features:

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• Have you written new tests for your core changes, as applicable?
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