Add pt-BR translation

[eribertomota]

Description

Add pt-BR translation

General checklist

• [x ] The commit is reviewed by yourself.
• [x ] The code is tested.
• [x ] Document is up to date or not necessary to be changed.
• [x ] The commit is compatible with repository's license.

[norihiro]

I'm sorry that I have not maintained the English translation file https://github.com/norihiro/obs-color-monitor/blob/main/data/locale/en-US.ini and your translation does not cover all the text. I will update the English translation file. I appreciate your interest in this plugin.

[eribertomota]

No problem. Thanks for your work.