Display group members to all users if it is public

lib/ui/screens/group_sections/group_members_screen.dart

@@ -58,7 +58,7 @@ class _GroupMembersSectionState extends State<GroupMembersSection> {
     return Stack(
       children: [
         ListView(children: _members.map(_buildGroupMemberTile).toList()),
-        _buildInvitationFAB()
+        _group.isAtLeastModerator ? _buildInvitationFAB() : Container()
       ],
     );
   }
@@ -172,7 +172,7 @@ class __GroupMembershipTileState extends State<_GroupMembershipTile> {
       subtitle: Text(_membershipLevels
           .firstWhere((f) => f.id == widget.membership.level)
           .title),
-      trailing: _buildTrailing(),
+      trailing: widget.group.isAtLeastModerator ? _buildTrailing() : null,
     );
   }