Remove old methods.

framework/src/Volo.Abp.Settings/Volo/Abp/Settings/NullSettingStore.cs

@@ -1,5 +1,4 @@
-using System.Collections.Generic;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.Abstractions;
 using Volo.Abp.DependencyInjection;
@@ -19,21 +18,5 @@ namespace Volo.Abp.Settings
         {
             return Task.FromResult((string) null);
         }
-
-        public Task SetAsync(string name, string value, string providerName, string providerKey)
-        {
-            Logger.LogWarning($"Setting the value for {name} is not possible because current setting store is {nameof(NullSettingStore)}");
-            return Task.CompletedTask;
-        }
-
-        public Task<List<SettingValue>> GetListAsync(string providerName, string providerKey)
-        {
-            return Task.FromResult(new List<SettingValue>());
-        }
-
-        public Task DeleteAsync(string name, string providerName, string providerKey)
-        {
-            return Task.CompletedTask;
-        }
     }
 }