[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* Remmove outdated server tests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/server.go

@@ -1364,12 +1364,6 @@ func (s *Server) doLicenseExpirationCheck() {
 		return
 	}
 
-	if license.IsCloud() {
-		appInstance := New(ServerConnector(s.Channels()))
-		appInstance.DoSubscriptionRenewalCheck()
-		return
-	}
-
 	users, err := s.Store().User().GetSystemAdminProfiles()
 	if err != nil {
 		mlog.Error("Failed to get system admins for license expired message from Mattermost.")