Removed the extra space in expected test result (#689)

* Removed the extra space in expected test result

Signed-off-by: Arash Rohani <Arash.Rohani@gmail.com>

* Changed the output match from exact to substring to fix the issue.

Signed-off-by: Arash Rohani <Arash.Rohani@gmail.com>

* Replaced the logger.LogInformation with Console.WriteLine to fix the test issue.

Signed-off-by: Arash Rohani <Arash.Rohani@gmail.com>

* Fixed the whitespace issue and added sleep directive

Signed-off-by: Arash Rohani <Arash.Rohani@gmail.com>

tutorials/pub-sub/README.md

@@ -506,6 +506,9 @@ expected_stdout_lines:
   - "A: Message on A"
   - "B: Message on B"
   - "C: Message on C"
+expected_stderr_lines:
+output_match_mode: substring
+sleep: 5
 -->
 
 ```bash

tutorials/pub-sub/csharp-subscriber/Program.cs

@@ -10,17 +10,17 @@ app.UseCloudEvents();
 app.MapSubscribeHandler();
 
 app.MapPost("/A", [Topic("pubsub", "A")] (ILogger<Program> logger, MessageEvent item) => {
-    logger.LogInformation($"{item.MessageType}: {item.Message}");
+    Console.WriteLine($"{item.MessageType}: {item.Message}");
     return Results.Ok();
 });
 
 app.MapPost("/B", [Topic("pubsub", "B")] (ILogger<Program> logger, MessageEvent item) => {
-    logger.LogInformation($"{item.MessageType}: {item.Message}");
+    Console.WriteLine($"{item.MessageType}: {item.Message}");
     return Results.Ok();
 });
 
 app.MapPost("/C", [Topic("pubsub", "C")] (ILogger<Program> logger, Dictionary<string, string> item) => {
-    logger.LogInformation($"{item["messageType"]}: {item["message"]}");
+    Console.WriteLine($"{item["messageType"]}: {item["message"]}");
     return Results.Ok();
 });