Added two courses R PT_BR (#7415)

* Added two courses R PT_BR

Hello! I'm trying to help by adding courses that helped me!

* fix: URL fragments goes in lowercase

* lint: leave 2 blank lines between listings and next heading

* Update courses/free-courses-pt_BR.md

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

* Update courses/free-courses-pt_BR.md

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>
Co-authored-by: Eric Hellman <eric@hellman.net>

courses/free-courses-pt_BR.md

@@ -33,6 +33,7 @@
 * [PHP](#php)
 * [Programação](#programação)
 * [Python](#python)
+* [R](#r)
 * [Raspberry Pi](#raspberry-pi)
 * [React Native](#react-native)
 * [Ruby](#ruby)
@@ -325,6 +326,12 @@
 * [Selenium com Python](https://www.youtube.com/playlist?list=PLOQgLBuj2-3LqnMYKZZgzeC7CKCPF375B) - Eduardo Mendes (YouTube)
 
 
+### R
+
+* [Curso de R com R Studio](https://www.youtube.com/playlist?list=PLzWDDw1w8cTS4i_B49WOWtjngjcMqTruG) - Escola de Inteligência Artificial
+* [Curso R para Iniciantes](https://www.youtube.com/playlist?list=PLyqOvdQmGdTQ5dE6hSD7ZGBu8bud70wYf) - Didática Tech
+
+
 ### Raspberry Pi
 
 * [Curso de Raspberry Pi: primeiros passos](https://www.youtube.com/playlist?list=PLHz_AreHm4dnGZ_nudmN4rvyLk2fHFRzy) - Gustavo Guanabara (YouTube)