add mangocast podcast from paraguay (#7943)

* add mangocast podcast from paraguay

* remove slash to end

* remove lines

* alphabetic order

casts/free-podcasts-screencasts-es.md

@@ -59,6 +59,7 @@
 ### Software Libre
 
 * [Compilando Podcast](https://compilando.audio) - Paco Estrada (podcast)
+* [Mangocast](https://www.mangocast.net) - Lucho Benitez, Pablo Santa Cruz, Miguel Balsevich, Luis Corvalán, Rolando Natalizia (podcast)
 * [Podcast Linux](https://podcastlinux.com) - Juan Febles (podcast)