IWorkflowMiddlewareErrorHandler never invoked

Hi all,

I have an ASP.NET Core 6 Web API project and registering the services in Startup.cs like below.
```
public void ConfigureServices(IServiceCollection services)
{
services.AddWorkflow();
services.AddTransient();

services.AddTransient();
services.AddTransient();
services.AddTransient();
services.AddTransient();
}
```
There are plenty of other dependencies registered of course. Below I am starting the workflow in the `Configure` method.
```
public void Configure(IWorkflowHost workflowHost, IHostApplicationLifetime hostApplicationLifetime)
{
hostApplicationLifetime.ApplicationStopping.Register(workflowHost.Stop);
workflowHost.RegisterWorkflow();
workflowHost.Start();
}
```
What I want to accomplish is any step throwing an exception to let it bubble up to the stack and be handled by ASP.NET Core (or in my case from a middleware in ASP.NET Core).

Here's my `IWorkflowMiddlewareErrorHandler` implementation.
```
public class WorkflowMiddlewareErrorHandler : IWorkflowMiddlewareErrorHandler
{
public Task HandleAsync(Exception ex)
{
throw ex; // this line of code never invoked.
}
}
```

Here's my workflow.
```
public class CitizenAdminDeleteAccountWorkflow : IWorkflow
{
public string Id => nameof(CitizenAdminDeleteAccountWorkflow);

public int Version => 1;

public void Build(IWorkflowBuilder builder)
{
builder
.Saga(saga => saga
.StartWith()
.Input((step, data) => step.Data = data)
.CompensateWith(compensate =>
compensate.Input((step, data) => step.Data = data))
.Then()
.Input((step, data) => step.Data = data)
)
.OnError(WorkflowErrorHandling.Terminate);
}
}
```
And a sample step.
```
public class DoInfluencerDeleteAccountStep : StepBodyAsync
{
public override async Task RunAsync(IStepExecutionContext context)
{
throw new DomainException("blah");

return ExecutionResult.Next();
}
}
```
Calling the workflow.
```
private readonly ISyncWorkflowRunner _runner;
var workflowInstance = await _runner.RunWorkflowSync(
nameof(CitizenAdminDeleteAccountWorkflow),
1,
new CitizenAdminDeleteAccountWorkflowData
{
Command = command,
CancellationToken = cancellationToken,
AppSettings = _appSettings
},
nameof(DeleteCitizenAdminAccountCommandHandler),
cancellationToken);
```
Any idea why the middleware isn't registered so that it will be invoked in any step exception and just let the program fail?