Create data transfer complete route

app/routes/data-transfer/complete.tsx

@@ -0,0 +1,10 @@
+import Success from "../../../components/Success.js";
+
+export default function () {
+  return (
+    <Success
+      heading="Data Transfer Submitted"
+      message="Your request is now being processed; this normally takes 1-2 weeks."
+    />
+  );
+}