Update robots.txt

Author: woodthom2

layouts/robots.txt

@@ -2,6 +2,4 @@ User-agent: *
 Allow: /
 
 Sitemap: https://harmonydata.ac.uk/sitemap.xml
-Sitemap: https://harmonydata.ac.uk/en/sitemap.xml
-Sitemap: https://harmonydata.ac.uk/pt/sitemap.xml
 Sitemap: https://harmonydata.ac.uk/search/sitemap.xml