Redirect to registration form from invite login

Issue: GREG-89

frontend/src/routes/index.tsx

-import React from 'react'
-import { Switch, Route } from 'react-router-dom'
+import React, { useEffect } from 'react'
+import { Switch, Route, useHistory } from 'react-router-dom'
 
 import { styled } from '@mui/system'
 import { CssBaseline } from '@mui/material'
 import fetchIntercept from 'fetch-intercept'
 
 import { useUserContext } from 'contexts'
+import { getCookie, deleteCookie } from 'utils'
 
 import Sponsor from 'routes/sponsor'
 import Register from 'routes/sponsor/register'
@@ -32,6 +33,16 @@ const AppWrapper = styled('div')({
 
 export default function App() {
   const { user, clearUserInfo } = useUserContext()
+  const history = useHistory()
+
+  useEffect( () => {
+    if (user.auth) {
+      const redirect = getCookie('redirect') || '/'
+      deleteCookie('redirect')
+      history.push(redirect)
+    }
+  }, [user.fetched])
+
 
   // Load country names for the supported languages
   registerLocale(i18n_iso_countries_en)

frontend/src/routes/invitelink/index.tsx

 import { useEffect } from 'react'
 import { Redirect } from 'react-router-dom'
-import { submitJsonOpts } from 'utils'
+import { submitJsonOpts, setCookie } from 'utils'
 
 function InviteLink() {
   // Fetch backend endpoint to preserve invite_id in backend session then redirect
@@ -11,6 +11,7 @@ function InviteLink() {
   useEffect(() => {
     fetch('/api/ui/v1/invitecheck/', submitJsonOpts('POST', { uuid: id }))
   }, [])
+  setCookie('redirect', 'guestregister')
   return <Redirect to="/invite" />
 }