Added account/newsletters link for member email preference

- adds new `/account/newsletters` portal link for member's to see their email preference
- redirects to signin if member is not logged in
- updates newsletter page for logged out members

ghost/portal/src/App.js

@@ -726,6 +726,10 @@ export default class App extends React.Component {
             return {
                 page: 'accountProfile'
             };
+        } else if (path === 'account/newsletters') {
+            return {
+                page: 'accountEmail'
+            };
         }
         return {};
     }

ghost/portal/src/components/pages/AccountEmailPage.js

@@ -7,14 +7,24 @@ const React = require('react');
 
 export default function AccountEmailPage() {
     const {member, onAction} = useContext(AppContext);
-    const defaultSubscribedNewsletters = [...(member.newsletters || [])];
+    const defaultSubscribedNewsletters = [...(member?.newsletters || [])];
     const [subscribedNewsletters, setSubscribedNewsletters] = useState(defaultSubscribedNewsletters);
+
+    useEffect(() => {
+        if (!member) {
+            onAction('switchPage', {
+                page: 'signin'
+            });
+        }
+    }, [member, onAction]);
+
     useEffect(() => {
         setSubscribedNewsletters(member?.newsletters || []);
-    }, [member.newsletters]);
+    }, [member?.newsletters]);
 
     return (
         <NewsletterManagement
+            notification={null}
             subscribedNewsletters={subscribedNewsletters}
             updateSubscribedNewsletters={(updatedNewsletters) => {
                 setSubscribedNewsletters(updatedNewsletters);