remove network dependency for Sitemap detection #1
Description
currently, in https://github.com/leonstafford/WordPressURLDetector/blob/main/src/DetectSitemaps.php, I'm making Guzzle requests to sitemap and robots.txt URLs. This makes things harder to test and the library more brittle.
Removing any network requests will ease usage, remove need to provide curl options for auth/ports, etc.
There should be an easier way to interrogate WP, Yoast, etc for the sitemap contents.