[typespec/azure-resource-manager] logical result path is undefined in ArmResourceActionAsync

When an async operation is performed using Azure-AsyncOperation, the final result of the operation is returned in the `properties` property in the `ArmOperationStatus` model, see the standards on ARM RPCs [here](https://github.com/Azure/azure-resource-manager-rpc/blob/master/v1.0/async-api-reference.md#azure-asyncoperation-resource-format)

For example, when I write:
```typespec
model Employee is TrackedResource {
...ResourceNameParameter;
}

model EmployeeProperties {
/** Age of employee */
age?: int32;
}

model Result {
/** Result of the action */
result: string;
}

op actionAsync is ArmResourceActionAsync;
```
it now gives us:
```
finalResult: Result
finalEnvelopeResult: Result
envelopeResult: ArmOperationStatus
finalResultPath: undefined
```

Should we have `finalResultPath` as `properties` here?

Start with the ArmResourceActionAsync and ArmOperationStatus definitions, then compare their result handling with the linked ARM asynchronous-operation standard. Done means the generated action metadata sets finalResultPath to properties and matches the reported result shape.

Written by the indexing model from the issue text.