Feature Highlights: move setting to a feature toggle (#44780) (#44827)

* Add toggle

* Use the toggle

* Cleanup

(cherry picked from commit a79c048344)

Co-authored-by: Alex Khomenko <Clarity-89@users.noreply.github.com>

pkg/api/frontendsettings.go

@@ -273,9 +273,6 @@ func (hs *HTTPServer) getFrontendSettingsMap(c *models.ReqContext) (map[string]i
 			"enabled": hs.Cfg.SectionWithEnvOverrides("recorded_queries").Key("enabled").MustBool(true),
 		},
 		"unifiedAlertingEnabled": hs.Cfg.UnifiedAlerting.Enabled,
-		"featureHighlights": map[string]bool{
-			"enabled": hs.SettingsProvider.Section("feature_highlights").KeyValue("enabled").MustBool(false),
-		},
 	}
 
 	if hs.Cfg.GeomapDefaultBaseLayerConfig != nil {