Allow changing past start dates of roles in webui

Roles that have started could not be given start dates in the past in
the frontend. After this fix they now can.

frontend/src/routes/sponsor/guest/guestRoleInfo/index.tsx

@@ -77,10 +77,7 @@ export default function GuestRoleInfo({ guest }: GuestRoleInfoProps) {
   const submit: SubmitHandler<RoleFormData> = (data) => {
     const payload: { start_date?: string; end_date: string } = {
       end_date: format(data.end_date as Date, 'yyyy-MM-dd'),
-    }
-    // Ignore start dates before today ()
-    if (data.start_date >= today) {
-      payload.start_date = format(data.start_date as Date, 'yyyy-MM-dd')
+      start_date: format(data.start_date as Date, 'yyyy-MM-dd'),
     }
 
     console.log('submitting', JSON.stringify(payload))