Intellisense doesn't show warning when missing required "properties" field

[SenthuranSivananthan]

Bicep version
Bicep CLI version 0.1.223-alpha (895cac2)

Describe the bug
When defining a vnet resource, the properties attribute isn't being marked as required. Per ARM template reference, properties is required: https://docs.microsoft.com/en-us/azure/templates/microsoft.network/virtualnetworks

Furthermore, the properties.addressSpace is required in order for deployment to complete.

To Reproduce

param location string = resourceGroup().location

resource vnet 'Microsoft.Network/virtualNetworks@2020-06-01' = {
    location: location
    name: 'vnet'
}

Types with issue (not exhaustive):

• Microsoft.Network/virtualNetworks@2020-06-01
• Microsoft.ContainerService/managedClusters@2020-09-01

Additional context

Expected

1. Intellisense warning
2. Error BCP035: The specified object is missing the following required properties

[alex-frankel]

Closing and tracking with #784