[MM-45053] - Remove 'trial of Mattermost ending soon' product emails (#20550)

* [MM-45053] - Remove 'trial of Mattermost ending soon' product emails

* remove trial end warning email

model/cloud.go

@@ -11,8 +11,6 @@ const (
 	EventTypeSendAdminWelcomeEmail        = "send-admin-welcome-email"
 	EventTypeSendUpgradeConfirmationEmail = "send-upgrade-confirmation-email"
 	EventTypeSubscriptionChanged          = "subscription-changed"
-	EventTypeTrialWillEnd                 = "trial-will-end"
-	EventTypeTrialEnded                   = "trial-ended"
 )
 
 var MockCWS string