Fix cache tests following #515's preserving URL change (#523)

Similar to #475, we weren't deleting the `MF-Original-URL` header
from incoming requests, leading to incorrect URLs in the loopback
server when the incoming request was passed-through as the cache key.

Tests also needed to be updated as the storage location is now based
off the actual URL passed to `dispatchFetch()`.

packages/miniflare/src/plugins/core/index.ts

@@ -145,6 +145,7 @@ export const SCRIPT_ENTRY = `async function handleEvent(event) {
     redirect: event.request.redirect,
     body: event.request.body,
   });
+  request.headers.delete("${HEADER_ORIGINAL_URL}");
 
   if (globalThis.${BINDING_SERVICE_USER} === undefined) {
     return new Response("No entrypoint worker found", { status: 404 });

packages/miniflare/test/plugins/cache/index.spec.ts

@@ -373,15 +373,14 @@ test.serial("operations persist cached data", async (t) => {
 	t.teardown(() => t.context.setOptions({}));
 
 	const key = "http://localhost/cache-persist";
-	const storedKey = new URL("/cache-persist", t.context.url).toString();
 
 	// Check put respects persist
 	await t.context.mf.dispatchFetch(key, {
 		method: "PUT",
 		headers: { "Test-Response-Cache-Control": "max-age=3600" },
 		body: "body",
 	});
-	let stored = await storage.get(storedKey);
+	let stored = await storage.get(key);
 	t.deepEqual(stored?.value, utf8Encode("body"));
 
 	// Check match respects persist
@@ -392,7 +391,7 @@ test.serial("operations persist cached data", async (t) => {
 	// Check delete respects persist
 	res = await t.context.mf.dispatchFetch(key, { method: "DELETE" });
 	t.is(res.status, 204);
-	stored = await storage.get(storedKey);
+	stored = await storage.get(key);
 	t.is(stored, undefined);
 });
 test.serial("operations are no-ops when caching disabled", async (t) => {