Update sidebar spanish to 3.5.2

Update the sidebar translation to 3.5.2

Author: kamekun

Modules/Translation/Resources/lang/core/es/sidebar.php

@@ -2,4 +2,5 @@
 
 return [
     'content' => 'Contenido',
+    'show group' => 'Mostrar Grupo barra lateral',
 ];