Checks the robots.txt file for the location of a sitemap.
A sitemap is an XML file that lists all of the important pages on a website. It is useful for search engines as it allows them to quickly discover all of these pages without crawling through the website. The sitemap also allows the website to tell the search engine how important the page is and how frequently it updates. This can be useful for SEO purposes.
A sitemap should be declared inside the robots.txt file so that search engines can find its location. This test checks to make sure your robots.txt file declares the location of a sitemap.