Also disabled the MainNavigationTests which do fail sometimes.

Author: pachlava

WordPress/WordPressUITests/WordPressUITests.xctestplan

@@ -29,6 +29,7 @@
         "LoginTests\/testSelfHostedUsernamePasswordLoginLogout()",
         "LoginTests\/testUnsuccessfulLogin()",
         "LoginTests\/testWpcomUsernamePasswordLogin()",
+        "MainNavigationTests",
         "ReaderTests",
         "SignupTests\/testEmailSignup()",
         "StatsTests",