Scenes deleting when restarting
<!-- Provide a general summary in the Title above -->

### Expected Behavior
Expected Behavior is when i restart homebridge my scenes relating to my homebridge accessories should retain.

### Current Behavior
Currently i only use tplink smarthome with homebridge.
On the Homekit app i create a screen with just the tplink accessories and it works. The problem comes when i restart Homebridge that scene is deleted but the accessories persist.

### Steps to Reproduce (for bugs)

- Add Accessories to homebridge
- Create scene with said accessories in homekit
- Restart Homebridge
- Previous created scene is deleted

### Versions
```
Docker Ubuntu
 node --version 
v14.16.0
homebridge --version
1.3.3
Ubuntu server 18.04
```
### Configuration
```
 {
            "name": "TplinkSmarthome",
            "addCustomCharacteristics": false,
            "deviceTypes": [
                "plug",
                "bulb"
            ],
            "devices": [
                {
                    "host": "192.168.10.30"
                },
                {
                    "host": "192.168.10.31"
                },
                {
                    "host": "192.168.10.32"
                },
                {
                    "host": "192.168.10.33"
                }
            ],
            "platform": "TplinkSmarthome"
        }
```

### Homebridge Log / Command Output
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-->
```
[3/16/2021, 12:46:02 PM] [HB Supervisor] Started Homebridge v1.3.3 with PID: 1577
Initializing HAP-NodeJS v0.9.3...
[3/16/2021, 12:46:03 PM] Loaded config.json with 0 accessories and 2 platforms.
[3/16/2021, 12:46:03 PM] Loaded 4 cached accessories from cachedAccessories.
[3/16/2021, 12:46:03 PM] ---
[3/16/2021, 12:46:04 PM] Disabled plugin: homebridge-dummy@0.5.0
[3/16/2021, 12:46:04 PM] ---
[3/16/2021, 12:46:04 PM] Loaded plugin: homebridge-tplink-smarthome@6.3.0
[3/16/2021, 12:46:04 PM] Registering platform 'homebridge-tplink-smarthome.TplinkSmarthome'
[3/16/2021, 12:46:04 PM] ---
[3/16/2021, 12:46:04 PM] Loaded plugin: homebridge-config-ui-x@4.40.0
[3/16/2021, 12:46:04 PM] Registering platform 'homebridge-config-ui-x.config'
[3/16/2021, 12:46:04 PM] ---
[3/16/2021, 12:46:04 PM] Loading 2 platforms...
[3/16/2021, 12:46:04 PM] [Config] Initializing config platform...
[3/16/2021, 12:46:04 PM] [Config] Running in Service Mode
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] Initializing TplinkSmarthome platform...
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] homebridge-tplink-smarthome v6.3.0, node v14.16.0, homebridge v1.3.3, api v2.7
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] Configuring cached accessory: [Living room Fan] UUID: 2b5e48e2-1dd5-4944-9485-e7dab4cdccdf deviceId: 800654BCF606658071617DE4F03D16671CF2C84C 
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] Configuring cached accessory: [Living room Back Lights] UUID: db858ce2-2a75-45a1-8004-3fe42d422ae6 deviceId: 80065A138746A2B798741E9FAA78183B1B7476D9 
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] Configuring cached accessory: [Dining Room Lights] UUID: ea46fe54-0d8f-47cf-a754-cab9b7af1261 deviceId: 800686EE96CEAF9C8A1C7ECF0C1813591B74FBD0 
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] Configuring cached accessory: [Living room Spot lights] UUID: cab6aa34-d2f2-44ac-9d26-fff8135a590c deviceId: 8006F58A4916A2BB8EF788E19F166DF01B74E0E0 
Preparing Advertiser for 'Homebridge 35B3 4413' using bonjour-hap backend!
                       
Starting to advertise 'Homebridge 35B3 4413' using bonjour-hap backend!
[3/16/2021, 12:46:04 PM] Homebridge v1.3.3 (Homebridge 35B3) is running on port 51957.
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] New Device Online: [Living room Fan] plug [800654BCF606658071617DE4F03D16671CF2C84C] 192.168.10.30 9999
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] Adding: [Living room Fan] plug [800654BCF606658071617DE4F03D16671CF2C84C]
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] New Device Online: [Living room Back Lights] plug [80065A138746A2B798741E9FAA78183B1B7476D9] 192.168.10.32 9999
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] Adding: [Living room Back Lights] plug [80065A138746A2B798741E9FAA78183B1B7476D9]
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] New Device Online: [Dining Room Lights] plug [800686EE96CEAF9C8A1C7ECF0C1813591B74FBD0] 192.168.10.33 9999
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] Adding: [Dining Room Lights] plug [800686EE96CEAF9C8A1C7ECF0C1813591B74FBD0]
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] New Device Online: [Living room Spot lights] plug [8006F58A4916A2BB8EF788E19F166DF01B74E0E0] 192.168.10.31 9999
[3/16/2021, 12:46:04 PM] [TplinkSmarthome] Adding: [Living room Spot lights] plug [8006F58A4916A2BB8EF788E19F166DF01B74E0E0]
```
