Enable `unmounts when dismissed` e2e

Hopefully increasing button size will eliminate flakyness

e2e/StaticLifecycleEvents.test.js

 const testIDs = require('../playground/src/testIDs');
 const { elementByLabel, elementById } = Utils;
 
-describe('static lifecycle events', () => {
+describe.only('static lifecycle events', () => {
   beforeEach(async () => {
     await device.relaunchApp();
   });
     await expect(elementByLabel('componentDidDisappear | navigation.playground.WelcomeScreen')).toBeVisible();
   });
 
-  xit('unmounts when dismissed', async () => {
+  it('unmounts when dismissed', async () => {
     await elementById(testIDs.PUSH_STATIC_LIFECYCLE_BUTTON).tap();
     await expect(elementByLabel('Static Lifecycle Events Overlay')).toBeVisible();
     await elementById(testIDs.DISMISS_BUTTON).tap();

playground/src/screens/StaticLifecycleOverlay.js

   },
   dismissBtn: {
     position: 'absolute',
-    width: 25,
-    height: 25,
+    width: 35,
+    height: 35,
     backgroundColor: 'white',
     justifyContent: 'center'
   },