fix(backend): お知らせのmetaタグ出力の条件が間違っていたのを修正 (#15377)

* fix(backend): お知らせのmetaタグ出力の条件が間違っていたのを修正

* Update Changelog

packages/backend/src/server/web/ClientServerService.ts

@@ -817,6 +817,7 @@ export class ClientServerService {
 		fastify.get<{ Params: { announcementId: string; } }>('/announcements/:announcementId', async (request, reply) => {
 			const announcement = await this.announcementsRepository.findOneBy({
 				id: request.params.announcementId,
+				userId: IsNull(),
 			});
 
 			if (announcement) {