[FEATURE] Support HubVirtualNetworkConnectionProperties ConnectivityStatus

### Feature Request

Support `HubVirtualNetworkConnectionProperties` struct `ConnectivityStatus` field.

```
type HubVirtualNetworkConnectionProperties struct {
ConnectivityStatus *ConnectivityStatus `json:"connectivityStatus,omitempty" azure:"ro"`
}
```

This field appears to be **undocumented** in the Azure REST API and even the Azure .NET SDK docs.
However, it's in the live response and portal.azure.com UI. I've tested 2 versions so far, and it's present in both:
* `2022-01-01`
* `2022-05-01`

```
{
"name": "",
"id": "",
"etag": "",
"type": "Microsoft.Network/virtualHubs/hubVirtualNetworkConnections",
"properties": {
"provisioningState": "Succeeded",
"resourceGuid": "",
"routingConfiguration": {
"associatedRouteTable": {
"id": ""
},
"propagatedRouteTables": {
"labels": [
"none"
],
"ids": [
{
"id": ""
}
]
},
"vnetRoutes": {
"staticRoutes": [],
"staticRoutesConfig": {
"propagateStaticRoutes": false,
"vnetLocalRouteOverrideCriteria": "Contains"
}
}
},
"remoteVirtualNetwork": {
"id": ""
},
"allowHubToRemoteVnetTransit": true,
"allowRemoteVnetToUseHubVnetGateways": true,
"enableInternetSecurity": true,
"connectivityStatus": "Connected"
}
}
```

cc: @juicybaba

Locate the Azure Network specification defining HubVirtualNetworkConnectionProperties and compare the 2022-01-01 and 2022-05-01 versions. Add the ConnectivityStatus field where appropriate, then validate the specification; done means the live connectivityStatus response is represented without breaking schema checks.

Written by the indexing model from the issue text.