Compatibility with the latest patches to xmlp.

1. SAXParser.parse now expects a ReadableStream.
2. SAXParser.parse now works on the input stream directly and closes it
   at the end

src/project/types/website/website-sitemap.ts

@@ -165,8 +165,7 @@ async function readSitemap(sitemapPath: string): Promise<Urlset> {
     }
   });
   const reader = await Deno.open(sitemapPath);
-  await parser.parse(reader);
-  reader.close();
+  await parser.parse(reader.readable);
   return urlset;
 }