Fix samples.

Fixes: #53
Fixes: #54

Author: galvesribeiro

test/Blazor.Extensions.SignalR.Test.Client/DemoData.cs

@@ -1,13 +1,23 @@
-using System;
-
-namespace Blazor.Extensions.SignalR.Test.Client
-{
-    public class DemoData
-    {
-        public long Id { get; set; }
-        public string Data { get; set; }
-        public decimal DecimalData { get; set; }
-        public DateTime DateTime { get; set; }
-        public bool Bool { get; set; }
-    }
-}
+using System;
+using System.Text.Json.Serialization;
+
+namespace Blazor.Extensions.SignalR.Test.Client
+{
+    public class DemoData
+    {
+        [JsonPropertyName("id")]
+        public long Id { get; set; }
+
+        [JsonPropertyName("data")]
+        public string Data { get; set; }
+
+        [JsonPropertyName("decimalData")]
+        public decimal DecimalData { get; set; }
+
+        [JsonPropertyName("dateTime")]
+        public DateTime DateTime { get; set; }
+
+        [JsonPropertyName("bool")]
+        public bool Bool { get; set; }
+    }
+}