[dashboard] do not async import dashboard actions on plugin load (ela…

…stic#195616)

Part of elastic#194171

Notice in the screen shot below, how opening Kibana home page loads
async dashboard chunks.
<img width="500" alt="Screenshot 2024-10-09 at 8 38 24 AM"
src="https://github.com/user-attachments/assets/2cfdb512-03e4-4634-bb0c-a8d163f98540">

This PR replaces async import with a sync import. The page load bundle
size increases but this is no different than the current behavior, just
the import is now properly accounted for in page load stats. The next
step is to resolve elastic#191642 and
reduce the page load impact of registering uiActions (but this is out of
scope for this PR).

(cherry picked from commit 7448376)

src/plugins/dashboard/public/plugin.tsx

@@ -78,6 +78,7 @@ import {
 } from './dashboard_container/panel_placement';
 import type { FindDashboardsService } from './services/dashboard_content_management_service/types';
 import { setKibanaServices, untilPluginStartServicesReady } from './services/kibana_services';
+import { buildAllDashboardActions } from './dashboard_actions';
 
 export interface DashboardFeatureFlagConfig {
   allowByValueEmbeddables: boolean;
@@ -322,14 +323,12 @@ export class DashboardPlugin
   public start(core: CoreStart, plugins: DashboardStartDependencies): DashboardStart {
     setKibanaServices(core, plugins);
 
-    Promise.all([import('./dashboard_actions'), untilPluginStartServicesReady()]).then(
-      ([{ buildAllDashboardActions }]) => {
-        buildAllDashboardActions({
-          plugins,
-          allowByValueEmbeddables: this.dashboardFeatureFlagConfig?.allowByValueEmbeddables,
-        });
-      }
-    );
+    untilPluginStartServicesReady().then(() => {
+      buildAllDashboardActions({
+        plugins,
+        allowByValueEmbeddables: this.dashboardFeatureFlagConfig?.allowByValueEmbeddables,
+      });
+    });
 
     return {
       locator: this.locator,