Tempo: remove backend migration feature toggle (#116054)

* remove unused frontend code

* remove feature toggle definition

* fix tests

pkg/services/featuremgmt/registry.go

@@ -1880,14 +1880,6 @@ var (
 			Expression:      "false",
 			RequiresRestart: true,
 		},
-		{
-			Name:            "tempoSearchBackendMigration",
-			Description:     "Run search queries through the tempo backend",
-			Stage:           FeatureStageGeneralAvailability,
-			Owner:           grafanaOSSBigTent,
-			Expression:      "false",
-			RequiresRestart: true,
-		},
 		{
 			Name:         "cdnPluginsLoadFirst",
 			Description:  "Prioritize loading plugins from the CDN before other sources",

pkg/services/featuremgmt/toggles_gen.csv

@@ -256,7 +256,6 @@ graphiteBackendMode,privatePreview,@grafana/partner-datasources,false,false,fals
 azureResourcePickerUpdates,GA,@grafana/partner-datasources,false,false,true
 prometheusTypeMigration,experimental,@grafana/partner-datasources,false,true,false
 pluginContainers,privatePreview,@grafana/plugins-platform-backend,false,true,false
-tempoSearchBackendMigration,GA,@grafana/oss-big-tent,false,true,false
 cdnPluginsLoadFirst,experimental,@grafana/plugins-platform-backend,false,false,false
 cdnPluginsUrls,experimental,@grafana/plugins-platform-backend,false,false,false
 pluginInstallAPISync,experimental,@grafana/plugins-platform-backend,false,false,false

pkg/services/featuremgmt/toggles_gen.go

@@ -742,10 +742,6 @@ const (
 	// Enables running plugins in containers
 	FlagPluginContainers = "pluginContainers"
 
-	// FlagTempoSearchBackendMigration
-	// Run search queries through the tempo backend
-	FlagTempoSearchBackendMigration = "tempoSearchBackendMigration"
-
 	// FlagCdnPluginsLoadFirst
 	// Prioritize loading plugins from the CDN before other sources
 	FlagCdnPluginsLoadFirst = "cdnPluginsLoadFirst"