IPublishPacket types is wrong definition?

[wh1tecat-nya]

In here, IPublishPacket description is this.

Only the topic property is mandatory.

But in /types/index.d.ts, IPublishPacket definition is this.

mqtt-packet/types/index.d.ts

Lines 64 to 81 in 2ac6d1b

	export interface IPublishPacket extends IPacket {
	cmd: 'publish'
	qos: QoS
	dup: boolean
	retain: boolean
	topic: string
	payload: string | Buffer
	properties?: {
	payloadFormatIndicator?: boolean,
	messageExpiryInterval?: number,
	topicAlias?: number,
	responseTopic?: string,
	correlationData?: Buffer,
	userProperties?: Object,
	subscriptionIdentifier?: number,
	contentType?: string
	}
	}

I think so key of qos, dup, retain, payload (and cmd) is need change to optional.

If this is correct, I can send PR.
Thanks.