add some golang books in spanish (#4906)

* add some golang books in spanish

* remove redundant part of the url
Co-authored-by: NSeth <seth@elypia.org>

* Add authors and resource type
Co-authored-by: NSeth <seth@elypia.org>

free-programming-books-es.md

@@ -165,6 +165,7 @@
 ### Go
 
 * [El pequeño libro Go](https://raulexposito.com/the-little-go-book-en-castellano.html) - Karl Seguin (HTML, PDF, EPUB)
+* [Go en Español](https://nachopacheco.gitbooks.io/go-es/content/doc) - Nacho Pacheco (HTML)
 
 
 ### Haskell