Skip tst_complete test in qquickanimationcontroller

This test sometimes fails.

Task-number: QTBUG-25967
Change-Id: Ic8f87e8ac44761b989f525fb1b90aa5df90abe6f
Reviewed-by: Yunqiao Yin <charles.yin@nokia.com>

tests/auto/quick/qquickanimationcontroller/data/tst_completion.qml

@@ -17,6 +17,8 @@ Rectangle {
     name:"AnimationController"
     when:windowShown
     function test_complete() {
+      skip("QTBUG-25967")
+
       ctrl.progress = 0;
       compare(rect.x, 0);
       ctrl.progress = 0.5;
@@ -40,4 +42,4 @@ Rectangle {
       compare(rect.x, 100);
     }
   }
-}
+}