add support for database list API 📢

Author: KoditkarVedant

Src/Notion.Client/DatabaseClient.cs

@@ -0,0 +1,33 @@
+using System.Threading.Tasks;
+
+namespace Notion.Client
+{
+    public interface IDatabaseClient
+    {
+        Task<PaginatedList<Database>> ListAsync();
+
+    }
+
+    public class DatabaseClient : IDatabaseClient
+    {
+        private readonly IRestClient _client;
+
+        public DatabaseClient(IRestClient client)
+        {
+            _client = client;
+        }
+
+        public async Task<PaginatedList<Database>> ListAsync()
+        {
+            try
+            {
+                return await _client.GetAsync<PaginatedList<Database>>("databases");
+            }
+            catch (System.Exception e)
+            {
+                // Todo: Throw Custom Exception
+                return null;
+            }
+        }
+    }
+}