Add URL fragment to the URL which contains redirect information; this f…

…ixes googlefonts/fontra#970

src/fontra_rcjk/landing.js

@@ -28,7 +28,7 @@ function rcjkAuthenticateFunc() {
   } else {
     const loginForm = document.querySelector("#login-form");
     const url = new URL(window.location);
-    loginForm.action = "/login" + url.search;
+    loginForm.action = "/login" + url.search + url.hash;
   }
   loginFailureMessage.classList.toggle("hidden", !loginFailed);
   return haveToken;