Merge pull request #2796 from madeline-underwood/robots.txt_update

Remove broken image sitemap reference from robots.txt

Author: pareenaverma

themes/arm-design-system-hugo-theme/layouts/robots.txt

@@ -23,6 +23,5 @@ Allow: /
 User-agent: CCBot
 Allow: /
 
-# Sitemaps help AI discovery
-Sitemap: https://learn.arm.com/sitemap.xml
-Sitemap: https://learn.arm.com/learn-image-sitemap.xml
+# Sitemap for page discovery
+Sitemap: https://learn.arm.com/sitemap.xml