 Siri wait a configurable amount of time before reporting back on Status?
### Backstory
Hi Alex
I'm using your plugin with Homebridge and also Nodered and everything is working well when I press the buttons within the Apple Home App, I can successfully shut down my win10 pc and also wake it up using WoL.

### Issue
However, When I use Siri voice commands to turn on and shutdown my win10 pc Siri is far too quick to reply complaining:- "Sorry I didn't hear back from your devices"; this may be because my PC takes approximately 20s to both completely startup and completely shutdown. i.e receive and lose ping replies.
Although everything is working Siri is always complaining because Siri is out of sync.

### Environment
* os & os version: FreeNAS-11.2-U7 in a FreeBSD jail.
* node version: Node.js v13.3.0
* homebridge version: Version 0.4.50
* homebridge-wol version: homebridge-wol v4.0.0

### Configuration
My configuration looks like this:
```
{
            "accessory": "NetworkDevice",
            "name": "simon-pc",
            "mac": "<mac-address>",
            "broadcastAddress": "172.16.28.254",
            "wakeGraceTime": 30,
            "shutdownGraceTime": 45,
            "ip": "172.16.28.6",
            "shutdownCommand": "ssh simon@simon-pc shutdown /s /f /t 0"
        },
```
### Notes
As you can see from my config above, I've been playing with the wakeGraceTime and shutdownGraceTime parameters in the hope that these parameters could fix the problem and slow down Siri from reporting back.; but this didn't work.

Is it possible to make Siri wait a configurable amount of time before reporting back on Status?