DualR3 switch issue
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### What issue do you have? Please be as thorough and explicit as possible.

I have installed a DUALR3 installed on a roller shutter. All works well with homebridge and homekit. I just installed a physical switch to it and there seems to be a tiny issue:
- when the shutter is closed, and I use the switch to open it, all works ok and homekit updates correctly according to the motor position.  
- when however the shutter is open and I use the switch to close it, homekit first sends me a notification saying the shutter is "opening" and then updates to the correct status once it is closed. 


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

Homebridge

* Which version of Homebridge/HOOBS do you have?

1.3.4


* 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.

Raspberry pi zero. 
Node.js: 14.17.6
NPM: 7.23.0

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

8.3.3

No the issue was also present in a previous version.  

* Which eWeLink devices do you have that are causing issues? Please include product models if applicable.

DUALR3

### Please paste any relevant logs below.
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```

[16/09/2021, 08:18:53] [eWeLink] [Bedroom Gate - New Wing] current power [0W] current voltage [239.74V] current current [0A].
[16/09/2021, 08:19:00] [eWeLink] [Bedroom Gate - New Wing] current position [88%].
[16/09/2021, 08:19:02] [eWeLink] [Bedroom Gate - New Wing] current position [76%].
[16/09/2021, 08:19:04] [eWeLink] [Bedroom Gate - New Wing] current position [64%].
[16/09/2021, 08:19:06] [eWeLink] [Bedroom Gate - New Wing] current position [53%].
[16/09/2021, 08:19:09] [eWeLink] [Bedroom Gate - New Wing] current position [41%].
[16/09/2021, 08:19:11] [eWeLink] [Bedroom Gate - New Wing] current position [29%].
[16/09/2021, 08:19:13] [eWeLink] [Bedroom Gate - New Wing] current position [18%].
[16/09/2021, 08:19:15] [eWeLink] [Bedroom Gate - New Wing] current position [6%].
[16/09/2021, 08:19:17] [eWeLink] [Bedroom Gate - New Wing] current position [0%].
[16/09/2021, 08:19:18] [eWeLink] [Bedroom Gate - New Wing] current target [0%].
[16/09/2021, 08:19:25] [eWeLink] [Bedroom Gate - New Wing] current power [409.72W] current voltage [242.8V] current current [1.68A].
[16/09/2021, 08:19:25] [eWeLink] [Bedroom Gate - New Wing] current power [409.72W] current voltage [242.8V] current current [1.68A].
[16/09/2021, 08:19:26] [eWeLink] [Bedroom Gate - New Wing] current position [11%].
[16/09/2021, 08:19:27] [eWeLink] [Bedroom Gate - New Wing] current power [411.29W] current voltage [241.95V] current current [1.75A].
[16/09/2021, 08:19:27] [eWeLink] [Bedroom Gate - New Wing] current power [411.29W] current voltage [241.95V] current current [1.75A].
[16/09/2021, 08:19:28] [eWeLink] [Bedroom Gate - New Wing] current position [22%].
[16/09/2021, 08:19:30] [eWeLink] [Bedroom Gate - New Wing] current position [34%].
[16/09/2021, 08:19:31] [eWeLink] [Bedroom Gate - New Wing] current power [412.86W] current voltage [241.87V] current current [1.75A].
[16/09/2021, 08:19:33] [eWeLink] [Bedroom Gate - New Wing] current position [46%].
[16/09/2021, 08:19:34] [eWeLink] [Bedroom Gate - New Wing] current position [57%].
[16/09/2021, 08:19:37] [eWeLink] [Bedroom Gate - New Wing] current position [69%].
[16/09/2021, 08:19:39] [eWeLink] [Bedroom Gate - New Wing] current position [81%].
[16/09/2021, 08:19:41] [eWeLink] [Bedroom Gate - New Wing] current position [92%].
[16/09/2021, 08:19:43] [eWeLink] [Bedroom Gate - New Wing] current position [100%].
[16/09/2021, 08:19:43] [eWeLink] [Bedroom Gate - New Wing] current power [0W] current voltage [240.24V] current current [0.04A].
[16/09/2021, 08:19:44] [eWeLink] [Bedroom Gate - New Wing] current power [0W] current voltage [240.24V] current current [0.04A].
[16/09/2021, 08:19:44] [eWeLink] [Bedroom Gate - New Wing] current target [100%].
[16/09/2021, 08:19:45] [eWeLink] [Bedroom Gate - New Wing] current power [0W] current voltage [241.19V] current current [0A].
[16/09/2021, 08:19:45] [eWeLink] [Bedroom Gate - New Wing] current power [0W] current voltage [241.19V] current current [0A].
[16/09/2021, 08:19:47] [eWeLink] [Bedroom Gate - New Wing] current power [0W] current voltage [241.16V] current current [0A].
[16/09/2021, 08:19:47] [eWeLink] [Bedroom Gate - New Wing] current power [0W] current voltage [241.16V] current current [0A].

```
