refactor: update script

* runs promises serially instead of running them all at once
* directly calls /new-episode route for latest episode

src/libs/promiseQueue.ts

@@ -0,0 +1,5 @@
+export async function promiseQueue(queue: (() => Promise<void>)[]) {
+  for (const promise of queue) {
+    await promise();
+  }
+}