Removed plugin imports

Signed-off-by: Andre Wanlin <awanlin@spotify.com>

packages/app-next/src/App.tsx

@@ -50,8 +50,6 @@ import {
 } from '@backstage/integration-react';
 import { createSignInPageExtension } from '@backstage/frontend-plugin-api';
 import { SignInPage } from '@backstage/core-components';
-import devToolsPlugin from '@backstage/plugin-devtools/alpha';
-import linguistPlugin from '@backstage/plugin-linguist/alpha';
 
 /*
 
@@ -127,8 +125,6 @@ const app = createApp({
     userSettingsPlugin,
     homePlugin,
     appVisualizerPlugin,
-    devToolsPlugin,
-    linguistPlugin,
     ...collectedLegacyPlugins,
     createExtensionOverrides({
       extensions: [