set default notification value

This should make it so that people who just joined have the default notification value as set by the guild instead of always defaulting to all messages.

src/util/entities/Member.ts

@@ -358,7 +358,7 @@ export class Member extends BaseClassWithoutId {
 					hide_muted_channels: false,
 					notify_highlights: 0,
 					channel_overrides: {},
-					message_notifications: 0,
+					message_notifications: guild.default_message_notifications,
 					mobile_push: true,
 					muted: false,
 					suppress_everyone: false,