Service Bus Output Binding is creating multiple messages from a JSON array when returning a string

Service bus output binding creating multiple messages when returning a string which is a JSON array. This has been noted since updating to **.Net 8** and using the **dotnet-isolated** function runtime. This behaviour has changed either between .Net upgrades or moving to isolated functions.

#### Repro steps

Run the following function:
```csharp
[Function("Test Func")]
[ServiceBusOutput("queuName", Connection = "ServiceBusConnectionString")]
public static async Task RunAsync(
[HttpTrigger(AuthorizationLevel.Anonymous, "post", Route = null)] HttpRequestData req)
{
return await req.ReadAsStringAsync();
}
```

Call with this JSON payload:
```json
[
{
"Test1": "test1"
},
{
"Test2": "test2"
}
]
```

#### Expected behavior

A message is created with the body:
```json
[
{
"Test1": "test1"
},
{
"Test2": "test2"
}
]
```

#### Actual behavior

Two messages are created:

1)
```
{
"Test1": "test1"
}
```
2)
```json
{
"Test2": "test2"
}
```

#### Related information

Provide any related information

* Programming language used: C#
* Bindings used: HttpTrigger - ServiceBusOutputBinding