The switch in Homekit is switched off although the status is "Shutting Down"
### Backstory
I want to use the wol plugin to shut down my piCorePlayer running on a Raspberry Pi. When the Pi is shut down, the socket (handled by Tuya-LAN) for the Pi should be switched off.

### Issue
When I am using the plugin to shut down my Pi the following happens:

> [TuyaAccessory] Sending piCorePlayer {"1":true}
>[4/29/2019, 9:03:57 PM] [Musikbox] NetworkDevice "Musikbox" (192.168.178.107) went from status "Offline" to "Online"
>[4/29/2019, 9:04:10 PM] [Musikbox] NetworkDevice shutdown cycle started for "Musikbox" (192.168.178.107)
>[4/29/2019, 9:04:10 PM] [Musikbox] Attempting to shut down "Musikbox" (192.168.178.107) using "sshpass -p 'xxxxx' ssh -oStrictHostKeyChecking=no tc@192.168.178.107 pcp bs"
>[4/29/2019, 9:04:10 PM] [Musikbox] NetworkDevice "Musikbox" (192.168.178.107) went from status "Online" to "Shutting Down"
>[TuyaAccessory] Sending piCorePlayer {"1":false}
>[4/29/2019, 9:04:56 PM] [Musikbox] NetworkDevice "Musikbox" (192.168.178.107) went from status "Shutting Down" to "Offline"

In the moment where I press the Button to shut Down the Pi the Button becomes switched off in Homekit, although the Pi is only in status "Shutting Down"
Isn't it possible to let the Button in Homekit set to off when the Pi is in status "Offline"?

### Environment
* os & os version: Raspbian 
* node version: 11.14.0
* homebridge version: 0.4.49
* homebridge-wol version: 3.2.4

### Configuration
My configuration looks like this:
        {
            "accessory": "NetworkDevice",
            "name": "Musikbox",
            "ip": "192.168.178.107",
            "pingInterval": 5,
            "shutdownGraceTime": 45,
            "shutdownCommand": "sshpass -p 'xxxxx' ssh -oStrictHostKeyChecking=no tc@192.168.178.107 pcp bs"
        },

I have omitted the Log, as you can see the Log above and there is no issue in not functioning or something like that.