remove the updated test

we're testing this with unit tests and this is being annoying in behat

tests/behat/admin-interface.feature

@@ -3,11 +3,6 @@ Feature: Adjust the Default Max Age setting
 Background:
 	Given I log in as an admin
 
-Scenario: Auto-update to the default value if the value
-	When I go to "/wp-admin/options-general.php?page=pantheon-cache"
-	Then I should see "The Pantheon GCDN cache max age has been updated. The previous value was 10 minutes. The new value is 1 week."
-	And the "pantheon-cache[default_ttl]" field should contain "604800"
-
 Scenario: Change the cache max age to 1 week
 	When I go to "/wp-admin/options-general.php?page=pantheon-cache"
 	And I fill in "pantheon-cache[default_ttl]" with "604800"