Update _config.yml

Exclude sitemap.xml from localization to avoid duplicate sitemap issue

Author: yunseo-kim

_config.yml

@@ -155,7 +155,7 @@ baseurl: ""
 # Polyglot Settings
 languages: ["en", "ko", "es", "pt-BR", "ja", "fr", "de"]
 default_lang: "en"
-exclude_from_localization: ["javascript", "images", "css", "public", "assets"]
+exclude_from_localization: ["javascript", "images", "css", "public", "assets", "sitemap"]
 parallel_localization: false
 lang_from_path: true