make rel=alternate a fully qualified url

Author: KianNH

src/components/overrides/Head.astro

@@ -182,7 +182,7 @@ head.push({
 	attrs: {
 		rel: "alternate",
 		type: "text/markdown",
-		href: Astro.url.pathname + "index.md",
+		href: Astro.site + Astro.url.pathname.slice(1) + "index.md",
 	},
 });
 

worker/index.worker.test.ts

@@ -327,7 +327,9 @@ describe("Cloudflare Docs", () => {
 					"link[rel='alternate'][type='text/markdown']",
 				)?.attributes.href;
 
-				expect(markdown).toBe("/workers/index.md");
+				expect(markdown).toBe(
+					"https://developers.cloudflare.com/workers/index.md",
+				);
 			});
 
 			it("og:image tag", () => {