Change "Newsletter" to "AMIV Announce" on profile.

We use this term everywhere else.

src/languages/de.js

@@ -133,8 +133,8 @@ export default {
       },
     },
     newsletter: {
-      unsubscribe: 'Vom Newsletter abmelden',
-      subscribe: 'Newsletter abonnieren',
+      unsubscribe: 'Vom AMIV Announce abmelden',
+      subscribe: 'AMIV Announce abonnieren',
     },
     sessions: {
       loading: 'Lade Sitzungsdaten',

src/languages/en.js

@@ -132,8 +132,8 @@ export default {
       },
     },
     newsletter: {
-      unsubscribe: 'Unsubscribe from Newsletter',
-      subscribe: 'Subscribe to Newsletter',
+      unsubscribe: 'Unsubscribe from AMIV Announce',
+      subscribe: 'Subscribe to AMIV Announce',
     },
     sessions: {
       loading: 'Loading session data',