ContainerApps@2022-03-01 cannot handle conditional registries

**Bicep version**
Bicep CLI version 0.8.9 (33a85174de)
and Bicep CLI version 0.9.1 (a2950a16df)

**Describe the bug**
I'm able to deploy a bicep file that creates a ContainerApp with a registry specified. However when I [make the registry property conditional](https://github.com/Gordonby/azure-quickstart-templates/blob/gb-containerAppRegistryIssue/quickstarts/microsoft.app/container-app-acr/main.bicep#L117), I get this error;

> "code": "ContainerAppInvalidSchema", "message": "Invalid request body for container app. Does not conform to Container App schema"

works;

```bicep
registries: [
{
identity: uai.id
server: acr.outputs.loginServer
}
]
```

also works;

```bicep
registries: []
```

causes the weird error;

```bicep
registries: someBooleanVar ? [] : [
{
identity: uai.id
server: acr.outputs.loginServer
}
]
```

Quite frustrating....

**To Reproduce**
Reproduceable from branch https://github.com/Gordonby/azure-quickstart-templates/blob/gb-containerAppRegistryIssue/quickstarts/microsoft.app/container-app-acr/main.bicep#L117

```bash
cd quickstarts\microsoft.app\container-app-acr
az group create -n innerloopeastus -l eastus
az deployment group create -g innerloopeastus -f .\main.bicep
```

Reproduce the issue from quickstarts/microsoft.app/container-app-acr/main.bicep around line 117 using the listed az group create and az deployment group create commands. Compare the concrete registries array, empty array, and conditional form; done means the conditional form deploys without the ContainerAppInvalidSchema error.

Written by the indexing model from the issue text.