improve newsletter wording

templates/emails/com/newsletter/mobile-darkmode.html

@@ -83,8 +83,8 @@
   {% endcall %}
 
   {% call text() %}
-    We want to say thank you to all users who have helped to improve SimpleLogin code and even
-    contribute important features.
+    On behalf of the team, I want to say thank you to all users who have helped to improve SimpleLogin code
+    and even contribute important features.
     That means a lot to us as SimpleLogin is after all an open-source project.
 
   {% endcall %}