mod_push: Set 'last-message-sender' to bare JID

If the mod_push option 'include_sender' is set to 'true', use the bare
JID rather than the full JID for the 'last-message-sender' field.

src/mod_push.erl

@@ -682,7 +682,7 @@ drop_online_sessions(LUser, LServer, Clients) ->
 
 -spec make_summary(binary(), xmpp_element() | xmlel() | none, direction())
       -> xdata() | undefined.
-make_summary(Host, #message{from = From} = Pkt, recv) ->
+make_summary(Host, #message{from = From0} = Pkt, recv) ->
     case {mod_push_opt:include_sender(Host),
 	  mod_push_opt:include_body(Host)} of
 	{false, false} ->
@@ -702,6 +702,7 @@ make_summary(Host, #message{from = From} = Pkt, recv) ->
 			      end,
 		    Fields2 = case IncludeSender of
 				  true ->
+				      From = jid:remove_resource(From0),
 				      [{'last-message-sender', From} | Fields1];
 				  false ->
 				      Fields1