Remove Atlas OSB from sitemap-index.xml (#72)

Author: sophstad

static/sitemap-index.xml

@@ -3,9 +3,6 @@
     <sitemap>
       <loc>https://docs.atlas.mongodb.com/sitemap.xml</loc>
     </sitemap>
-    <sitemap>
-      <loc>https://docs.mongodb.com/atlas-open-service-broker/sitemap.xml</loc>
-    </sitemap>
     <sitemap>
       <loc>https://docs.mongodb.com/bi-connector/current/sitemap.xml</loc>
     </sitemap>