Portal does not set the default value of bool parameters if it is false

When creating an environment from an ARM template using the DevTest Labs portal, the default value of bool parameters is not set if `defaultValue` is `false` (it works fine if `defaultValue` is `true`).

This example allows to reproduce the issue:

```json
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"boolParam1": {
"type": "bool",
"defaultValue": true,
"metadata": {
"description": "Portal will set the default value to true as expected."
}
},
"boolParam2": {
"type": "bool",
"defaultValue": false,
"metadata": {
"description": "Portal will not set the default value."
}
}
},
"variables": {
},
"resources": [
],
"outputs": {
}
}
```

The default value is always set as expected when loading the template with .

Picture of the issue (parameter `boolParam2` is not set):