MM-15021: Adding new builtin system schema for Guests (#10601)

* MM-15021: Adding new builtin system schema for Guests

* Fixing tests

* Setting properly the permissions

* Adding guests to sampledata

* Restrict more roles updates in the app layer for guests

* Adding comment to explain that permissions migration must go at the end

* Setting the default guest role for custom scheme during migration

* Fixing import and export

* Creating scheme guest roles on migration

* Fixing tests

* Fixing tests

* Fixing tests

migrations/helper_test.go

@@ -63,8 +63,7 @@ func setupTestHelper(enterprise bool) *TestHelper {
 
 	th.App.UpdateConfig(func(cfg *model.Config) { *cfg.ServiceSettings.ListenAddress = prevListenAddress })
 
-	th.App.DoAdvancedPermissionsMigration()
-	th.App.DoEmojisPermissionsMigration()
+	th.App.DoAppMigrations()
 
 	th.App.Srv.Store.MarkSystemRanUnitTests()