update instalation.md

adding needed settings after plugin update to version 0.7.0

Signed-off-by: Gio <6011354+gioufop@users.noreply.github.com>

docs/features/kubernetes/installation.md

@@ -62,13 +62,16 @@ add the following:
 import { KubernetesBuilder } from '@backstage/plugin-kubernetes-backend';
 import { Router } from 'express';
 import { PluginEnvironment } from '../types';
+import { CatalogClient } from '@backstage/catalog-client';
 
 export default async function createPlugin(
   env: PluginEnvironment,
 ): Promise<Router> {
+  const catalogApi = new CatalogClient({ discoveryApi: env.discovery });
   const { router } = await KubernetesBuilder.createBuilder({
     logger: env.logger,
     config: env.config,
+    catalogApi,
   }).build();
   return router;
 }