Plugins: Forbid loading Angular plugins when Angular is disabled (#69679)

* Plugins: Forbid loading Angular plugins when Angular is disabled

* Plugins: Made angulardetector a service, add tests for angular loader cases

* Fix missing import

* Add nolint:gocyclo to loadPlugins

pkg/services/pluginsintegration/config/config.go

@@ -41,6 +41,7 @@ func ProvideConfig(settingProvider setting.Provider, grafanaCfg *setting.Cfg, fe
 		grafanaCfg.PluginsCDNURLTemplate,
 		tracingCfg,
 		featuremgmt.ProvideToggles(features),
+		grafanaCfg.AngularSupportEnabled,
 	), nil
 }