Add integration test for bug fix

Author: KoditkarVedant

Test/Notion.IntegrationTests/IPageClientTests.cs

@@ -54,5 +54,57 @@ public async Task CreateAsync_CreatesANewPage()
                 Archived = true
             });
         }
+
+        [Fact]
+        public async Task Bug_unable_to_create_page_with_select_property()
+        {
+            var options = new ClientOptions
+            {
+                AuthToken = Environment.GetEnvironmentVariable("NOTION_AUTH_TOKEN")
+            };
+
+            INotionClient _client = new NotionClient(options);
+
+            PagesCreateParameters pagesCreateParameters = PagesCreateParametersBuilder.Create(new DatabaseParentInput
+            {
+                DatabaseId = "f86f2262-0751-40f2-8f63-e3f7a3c39fcb"
+            })
+            .AddProperty("Name", new TitlePropertyValue
+            {
+                Title = new List<RichTextBase>
+                {
+                    new RichTextText
+                    {
+                        Text = new Text
+                        {
+                            Content = "Test Page Title"
+                        }
+                    }
+                }
+            })
+            .AddProperty("TestSelect", new SelectPropertyValue
+            {
+                Select = new SelectOption
+                {
+                    Id = "dfbfbe65-6f67-4876-9f75-699124334d06"
+                }
+            })
+            .Build();
+
+            var page = await _client.Pages.CreateAsync(pagesCreateParameters);
+
+            page.Should().NotBeNull();
+            page.Parent.Should().BeOfType<DatabaseParent>().Which
+                .DatabaseId.Should().Be("f86f2262-0751-40f2-8f63-e3f7a3c39fcb");
+
+            page.Properties.Should().ContainKey("Name");
+            page.Properties["Name"].Should().BeOfType<TitlePropertyValue>().Which
+                .Title.First().PlainText.Should().Be("Test Page Title");
+
+            await _client.Pages.UpdateAsync(page.Id, new PagesUpdateParameters
+            {
+                Archived = true
+            });
+        }
     }
 }