refactor(search-backend): use credential for authorized search engines

Signed-off-by: Camila Belo <camilaibs@gmail.com>

packages/backend/package.json

@@ -72,7 +72,6 @@
     "@backstage/plugin-search-backend-module-pg": "workspace:^",
     "@backstage/plugin-search-backend-module-techdocs": "workspace:^",
     "@backstage/plugin-search-backend-node": "workspace:^",
-    "@backstage/plugin-search-common": "workspace:^",
     "@backstage/plugin-signals-backend": "workspace:^",
     "@backstage/plugin-signals-node": "workspace:^",
     "@backstage/plugin-tech-insights-backend": "workspace:^",

packages/backend/src/plugins/search.ts

@@ -23,9 +23,9 @@ import { ElasticSearchSearchEngine } from '@backstage/plugin-search-backend-modu
 import { PgSearchEngine } from '@backstage/plugin-search-backend-module-pg';
 import {
   IndexBuilder,
+  SearchEngine,
   LunrSearchEngine,
 } from '@backstage/plugin-search-backend-node';
-import { SearchEngine } from '@backstage/plugin-search-common';
 import { DefaultTechDocsCollatorFactory } from '@backstage/plugin-search-backend-module-techdocs';
 import { Router } from 'express';
 import { PluginEnvironment } from '../types';
@@ -117,6 +117,7 @@ export default async function createPlugin(
   return await createRouter({
     engine: indexBuilder.getSearchEngine(),
     types: indexBuilder.getDocumentTypes(),
+    discovery: env.discovery,
     permissions: env.permissions,
     config: env.config,
     logger: env.logger,