fix: Fixed CommandExecuted firing twice for failed RuntimeResults (#1192)

* Fixed CommandExecuted firing twice for failed RuntimeResults

* Changed to just checking the result type

* Amendments

src/Discord.Net.Commands/CommandService.cs

@@ -603,7 +603,7 @@ namespace Discord.Commands
             //If we get this far, at least one parse was successful. Execute the most likely overload.
             var chosenOverload = successfulParses[0];
             var result = await chosenOverload.Key.ExecuteAsync(context, chosenOverload.Value, services).ConfigureAwait(false);
-            if (!result.IsSuccess) // succesful results raise the event in CommandInfo#ExecuteInternalAsync (have to raise it there b/c deffered execution)
+            if (!result.IsSuccess && !(result is RuntimeResult)) // succesful results raise the event in CommandInfo#ExecuteInternalAsync (have to raise it there b/c deffered execution)
                 await _commandExecutedEvent.InvokeAsync(chosenOverload.Key.Command, context, result);
             return result;
         }