Plugins: Angular deprecation: Fix AngularDeprecationNotice not being rendered on first page load (#83221)

* Plugins: Angular deprecation: Wait for plugins to be inizialized before rendering AngularDeprecationNotice

* use then

* fix tests

* mockCleanUpDashboardAndVariables.mockReset();

* Handle plugin not found

* PR review feedback

* Add comment

* removed unnecessary return

* PR review feedback

* Use grafanaBootData

* Removed comments

* fix tests

* Use config for hideDeprecation as well

public/app/features/dashboard/state/DashboardModel.ts

@@ -1338,7 +1338,9 @@ export class DashboardModel implements TimeModel {
   hasAngularPlugins(): boolean {
     return this.panels.some((panel) => {
       // Return false for plugins that are angular but have angular.hideDeprecation = false
-      const isAngularPanel = panel.isAngularPlugin() && !panel.plugin?.meta.angular?.hideDeprecation;
+      // We cannot use panel.plugin.isAngularPlugin() because panel.plugin may not be initialized at this stage.
+      const isAngularPanel =
+        config.panels[panel.type]?.angular?.detected && !config.panels[panel.type]?.angular?.hideDeprecation;
       let isAngularDs = false;
       if (panel.datasource?.uid) {
         isAngularDs = isAngularDatasourcePluginAndNotHidden(panel.datasource?.uid);