Document Portuguese translation team

Please document

* git repositories of translators on the newly created page contribute/how/translate/language_team_pt-br
* Glossaries used by the portuguese team on that same page

Related issues

Related to #7556 (closed)
Related to #6968 (closed)

Original created by @u on 8085 (Redmine)

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information