Clarify test for pointerrawupdate (#46951)

pointerevents/pointerevent_pointerrawupdate.html

@@ -19,7 +19,7 @@ <h4>Test Description: This test checks that pointerrawupdate is not dispatched o
         <p>Press left button down and then press middle button while holding down left button. Then release the buttons</p>
         <div id="target0"></div>
         <script>
-            var test_pointerrawupdate = async_test("pointerrawupdate event received");
+            var test_pointerrawupdate = async_test("pointerrawupdate event not received");
             var actions_promise;
 
             var pointerrawupdateReceived = false;