[CLD-7421][CLD-7420] Deprecate Self Serve: First Pass (#26668)

* Deprecate Self Serve: First Pass

* Fix ci

* Fix more ci

* Remmove outdated server tests

* Fix a missed spot opening purchase modal in Self Hosted

* Fix i18n

* Clean up some more server code, fix webapp test

* Fix alignment of button

* Fix linter

* Fix i18n server side

* Add back translation

* Remove client functions

* Put back client functions

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

server/channels/app/email/service.go

@@ -134,7 +134,6 @@ type ServiceInterface interface {
 	SendVerifyEmail(userEmail, locale, siteURL, token, redirect string) error
 	SendSignInChangeEmail(email, method, locale, siteURL string) error
 	SendWelcomeEmail(userID string, email string, verified bool, disableWelcomeEmail bool, locale, siteURL, redirect string) error
-	SendCloudUpgradeConfirmationEmail(userEmail, name, trialEndDate, locale, siteURL, workspaceName string, isYearly bool, embeddedFiles map[string]io.Reader) error
 	SendCloudWelcomeEmail(userEmail, locale, teamInviteID, workSpaceName, dns, siteURL string) error
 	SendPasswordChangeEmail(email, method, locale, siteURL string) error
 	SendUserAccessTokenAddedEmail(email, locale, siteURL string) error
@@ -147,19 +146,6 @@ type ServiceInterface interface {
 	SendNotificationMail(to, subject, htmlBody string) error
 	SendMailWithEmbeddedFiles(to, subject, htmlBody string, embeddedFiles map[string]io.Reader, messageID string, inReplyTo string, references string, category string) error
 	SendLicenseUpForRenewalEmail(email, name, locale, siteURL, ctaTitle, ctaLink, ctaText string, daysToExpiration int) error
-	SendPaymentFailedEmail(email string, locale string, failedPayment *model.FailedPayment, planName, siteURL string) (bool, error)
-	// Cloud delinquency email sequence
-	SendDelinquencyEmail7(email, locale, siteURL, planName string) error
-	SendDelinquencyEmail14(email, locale, siteURL, planName string) error
-	SendDelinquencyEmail30(email, locale, siteURL, planName string) error
-	SendDelinquencyEmail45(email, locale, siteURL, planName, delinquencyDate string) error
-	SendDelinquencyEmail60(email, locale, siteURL string) error
-	SendDelinquencyEmail75(email, locale, siteURL, planName, delinquencyDate string) error
-	SendDelinquencyEmail90(email, locale, siteURL string) error
-	SendCloudRenewalEmail60(email, locale, siteURL string) error
-	SendCloudRenewalEmail30(email, locale, siteURL string) error
-	SendCloudRenewalEmail7(email, locale, siteURL string) error
-	SendNoCardPaymentFailedEmail(email string, locale string, siteURL string) error
 	SendRemoveExpiredLicenseEmail(ctaText, ctaLink, email, locale, siteURL string) error
 	AddNotificationEmailToBatch(user *model.User, post *model.Post, team *model.Team) *model.AppError
 	GetMessageForNotification(post *model.Post, teamName, siteUrl string, translateFunc i18n.TranslateFunc) string