Missing information - Internal API - POWR320D (ewUUID 190)
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### What issue do you have? Please be as thorough and explicit as possible.
Internal API do not reply with Power, Current and Voltage of the accessory Sonoff POWR320D (eweUUID 190).

```json
{
    "success": true,
    "response": {
        "status": {
            "wan": true,
            "lan": false,
            "ip": false
        },
        "services": [
            "switch",
            "power"
        ],
        "switch": {
            "state": "on"
        }
        ......MISSING_POWER_HERE......
    }
}
```

The current values are printed to logs:
```bash
[3/26/2024, 5:13:18 PM] [eWeLink] [POWR320D] current power [73.13W] current voltage [125.72V] current current [0.78A].
[3/26/2024, 5:13:22 PM] [eWeLink] [POWR320D] current power [76.65W] current voltage [125.72V] current current [0.77A].
[3/26/2024, 5:13:24 PM] [eWeLink] [POWR320D] current power [72.81W] current voltage [125.56V] current current [0.8A].
```

I noticed that those characteristics are removed to that eweUUID: https://github.com/bwp91/homebridge-ewelink/blob/9f0bef581abdf0db9c382d12abfcff3ac0531faf/lib/device/switch-single.js#L79-L87

And consequently not showing: https://github.com/bwp91/homebridge-ewelink/blob/9f0bef581abdf0db9c382d12abfcff3ac0531faf/lib/device/switch-single.js#L291-L299

It's a bug or i'm not seeing the big picture?

### Details of your setup.
* Do you use (1) Homebridge UI-X (2) Homebridge CLI or (3) HOOBS? 
(1) Homebridge UI-X 4.55.1


* Which version of Homebridge/HOOBS do you have?
Homebridge v1.7.0


* Which platform do you run Homebridge/HOOBS on (e.g. Raspberry Pi/Windows/HOOBS Box)? Please also mention your version of Node.js/NPM if known.
Docker


* Which version of this plugin (homebridge-ewelink) do you have? Has the issue started since upgrading from a previous version?
12.1.0


* Which eWeLink devices do you have that are causing issues? Please include product models if applicable.
Sonoff POWR320D (eweUUID 190)


### Please paste any relevant logs below.
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```
[3/26/2024, 5:52:16 PM] Homebridge v1.7.0 (HAP v0.11.2) (Homebridge ECEB) is running on port 51609.
[3/26/2024, 5:52:17 PM] [Homebridge UI] [HapClient] Discovery :: Found HAP device with username 0E:F4:6D:63:EC:EB
[3/26/2024, 5:52:17 PM] [Homebridge UI] [HapClient] Discovery :: Testing 0E:F4:6D:63:EC:EB via http://172.19.0.2:51609/accessories
[3/26/2024, 5:52:17 PM] [Homebridge UI] [HapClient] Discovery :: Success 0E:F4:6D:63:EC:EB via http://172.19.0.2:51609/accessories
[3/26/2024, 5:52:17 PM] [Homebridge UI] [HapClient] Discovery :: [172.19.0.2:51609 (0E:F4:6D:63:EC:EB)] Instance Registered
[3/26/2024, 5:52:21 PM] [eWeLink] Fetching devices from eWeLink home/id [My Home] [5ed90d89c35d3d0008aec5b3].
[3/26/2024, 5:52:28 PM] [eWeLink] LAN monitoring started.
[3/26/2024, 5:52:28 PM] [eWeLink] [POWR320D] initialising with options {"inUsePowerThreshold":0,"logging":"standard","showAs":"default"}.
[3/26/2024, 5:52:28 PM] [homebridge-ewelink] This plugin generated a warning from the characteristic 'Voltage': Characteristic not in required or optional characteristic section for service Switch. Adding anyway.. See https://homebridge.io/w/JtMGR for more info.
[3/26/2024, 5:52:28 PM] [homebridge-ewelink] This plugin generated a warning from the characteristic 'Electric Current': Characteristic not in required or optional characteristic section for service Switch. Adding anyway.. See https://homebridge.io/w/JtMGR for more info.
[3/26/2024, 5:52:28 PM] [eWeLink] [POWR320D] initialised and LAN mode unavailable as not discovered/supported [190:POWR320D].
[3/26/2024, 5:52:28 PM] [eWeLink] ✓ Setup complete. This plugin has been made with ♥ by bwp91, please consider a ☆ on GitHub if you are finding it useful!
[3/26/2024, 5:52:28 PM] [eWeLink] Internal API listening on port [9591].
[3/26/2024, 5:52:28 PM] [eWeLink] [POWR320D] current power [74.35W] current voltage [126.45V] current current [0.82A].
[3/26/2024, 5:52:33 PM] [eWeLink] [POWR320D] current power [75.89W] current voltage [126.45V] current current [0.82A].
[3/26/2024, 5:52:34 PM] [Homebridge UI] [HapClient] Discovery :: Ended
[3/26/2024, 5:52:34 PM] [eWeLink] [POWR320D] current power [76.4W] current voltage [126.61V] current current [0.82A].
[3/26/2024, 5:52:38 PM] [eWeLink] [POWR320D] current power [72.56W] current voltage [126.54V] current current [0.82A].
[3/26/2024, 5:52:40 PM] [eWeLink] [POWR320D] current power [79.18W] current voltage [126.73V] current current [0.83A].
```
