Disable flaky test

test_activateEventSend hasn't run in a while due to a
test condition error (see eclipse-platform#2591). Therefore
we are going to disable this test that is a feature
only on GTK3/x11

Author: jonahgraham

tests/org.eclipse.swt.tests/JUnit Tests/org/eclipse/swt/tests/junit/Test_org_eclipse_swt_widgets_Shell.java

@@ -43,6 +43,7 @@
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.swt.widgets.Text;
 import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
 /**
@@ -652,6 +653,7 @@ public void test_setBoundsLorg_eclipse_swt_graphics_Rectangle() {
  * Regression test for Bug 436841 - [GTK3] FocusOut/In and Activate/Deactivate
  * events when opening context menu. Only applicable on GTK x11.
  */
+@Disabled(value = "Test works fine most of the time, but it flaky. Due to issue described in https://github.com/eclipse-platform/eclipse.platform.swt/pull/2591 the test hasn't really run a in long time")
 @Test
 public void test_activateEventSend() throws InterruptedException {
 	if (SwtTestUtil.isGTK && SwtTestUtil.isX11.getAsBoolean()) {