自分のノートにリアクションを押せるように (#6506)

* resolve #6468

* リモートから来たセルフリアクションの対応

src/services/note/reaction/create.ts

@@ -15,11 +15,6 @@ import { createNotification } from '../../create-notification';
 import deleteReaction from './delete';
 
 export default async (user: User, note: Note, reaction?: string) => {
-	// Myself
-	if (note.userId === user.id) {
-		throw new IdentifiableError('2d8e7297-1873-4c00-8404-792c68d7bef0', 'cannot react to my note');
-	}
-
 	reaction = await toDbReaction(reaction, user.host);
 
 	const exist = await NoteReactions.findOne({