Loki Queries: Query Splitting enabled by default (#75876)

* Loki Query Splitting: enable by default

* Query splitting: add gdev dashboard

* Update testdata file

* Update devenv/dev-dashboards/datasource-loki/loki_query_splitting.json

Co-authored-by: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com>

* Revert "Update testdata file"

This reverts commit 5a891ba1f2.

* Update feature-toggles readme

---------

Co-authored-by: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com>

pkg/services/featuremgmt/registry.go

@@ -301,9 +301,10 @@ var (
 		{
 			Name:         "lokiQuerySplitting",
 			Description:  "Split large interval queries into subqueries with smaller time intervals",
-			Stage:        FeatureStageExperimental,
+			Stage:        FeatureStageGeneralAvailability,
 			FrontendOnly: true,
 			Owner:        grafanaObservabilityLogsSquad,
+			Expression:   "true", // turned on by default
 		},
 		{
 			Name:         "lokiQuerySplittingConfig",

pkg/services/featuremgmt/toggles_gen.csv

@@ -42,7 +42,7 @@ alertingBacktesting,experimental,@grafana/alerting-squad,false,false,false,false
 editPanelCSVDragAndDrop,experimental,@grafana/grafana-bi-squad,false,false,false,true
 alertingNoNormalState,preview,@grafana/alerting-squad,false,false,false,false
 logsContextDatasourceUi,GA,@grafana/observability-logs,false,false,false,true
-lokiQuerySplitting,experimental,@grafana/observability-logs,false,false,false,true
+lokiQuerySplitting,GA,@grafana/observability-logs,false,false,false,true
 lokiQuerySplittingConfig,experimental,@grafana/observability-logs,false,false,false,true
 individualCookiePreferences,experimental,@grafana/backend-platform,false,false,false,false
 gcomOnlyExternalOrgRoleSync,GA,@grafana/grafana-authnz-team,false,false,false,false