[gimp-web] content: remove language in the newly added books.

[Jehan <jehanp src gnome org>]

commit 98528ca75d91231c3a562b3f6ae01c66f744ca76
Author: Jehan <jehan girinstud io>
Date:   Fri Jun 10 16:42:25 2022 +0200

    content: remove language in the newly added books.
    
    Since it's now in per-language subsection, this info is redundant.

 content/books/index.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/content/books/index.md b/content/books/index.md
index 1971640a..30eb526b 100644
--- a/content/books/index.md
+++ b/content/books/index.md
@@ -233,7 +233,7 @@ The exercise photos in the book are available to download for the reader to foll
 
 ## Español / Spanish
 
-### Blanco y Negro con GIMP (2 ed.) (Español / Spanish)
+### Blanco y Negro con GIMP (2 ed.)
 
 ![Blanco y Negro con GIMP](BYNG2022_frente.jpg)
 
@@ -251,7 +251,7 @@ The exercise photos in the book are available to download for the reader to foll
 - Múltiples ejemplos descritos paso a paso
 - Un nuevo anexo dedicado al color creativo
 
-### Niveles y Curvas con GIMP (2 ed.) (Español / Spanish)
+### Niveles y Curvas con GIMP (2 ed.)
 
 ![Niveles y Curvas con GIMP (2ed.)](NyC.jpg)