[Pub/sub subscriptions] Fix C# example (#2545)

* fix csharp example per hal

Signed-off-by: Hannah Hunter <hannahhunter@microsoft.com>

* update per Mark

Signed-off-by: Hannah Hunter <hannahhunter@microsoft.com>

* add second example

Signed-off-by: Hannah Hunter <hannahhunter@microsoft.com>

Co-authored-by: Mark Fussell <markfussell@gmail.com>

daprdocs/content/en/developing-applications/building-blocks/pubsub/subscription-methods.md

@@ -191,15 +191,25 @@ The programmatic approach returns the `routes` JSON structure within the code, u
 {{% codetab %}}
 
 ```csharp
-[Topic("pubsub", "checkout", event.type ==\"order\"")]
-[HttpPost("orders")]
-public async Task<ActionResult<Stock>> HandleCheckout(Checkout checkout, [FromServices] DaprClient daprClient)
+[Topic("pubsub", "orders")]
+[HttpPost("/checkout")]
+public async Task<ActionResult<Order>>Checkout(Order order, [FromServices] DaprClient daprClient)
 {
     // Logic
-    return stock;
+    return order;
 }
 ```
 
+or
+
+```csharp
+// Dapr subscription in [Topic] routes orders topic to this route
+app.MapPost("/checkout", [Topic("pubsub", "orders")] (Order order) => {
+    Console.WriteLine("Subscriber received : " + order);
+    return Results.Ok(order);
+});
+```
+
 {{% /codetab %}}
 
 {{% codetab %}}