chore: moves to ExpandoObject for updating entities because not all properties need to be part of the payload

tests/ClientsApiTests.cs

@@ -1,3 +1,4 @@
+using System.Dynamic;
 using System.Linq;
 using Novaloop.PaymoApi.Clients;
 using Novaloop.PaymoApi.Clients.Models;
@@ -84,7 +85,8 @@ namespace Novaloop.PaymoApi.Tests
         {
             // Arrange
             var createdClient = await _clientsApi.CreateClient(_testClient);
-            var clientUpdateInfo = new Client {Name = "Updated"};
+            dynamic clientUpdateInfo = new ExpandoObject();
+            clientUpdateInfo.Name = "Updated";
 
             // Act
             await _clientsApi.UpdateClient(clientUpdateInfo, createdClient.Id);