Make onLoaderStart and onLoadError optional (#108)

Author: jorgea-stripe

src/Components.tsx

@@ -3,8 +3,8 @@ import {useUpdateWithSetter} from './utils/useUpdateWithSetter';
 import {LoadError, LoaderStart, NotificationCount} from '@stripe/connect-js';
 
 export type CommonComponentProps = {
-  onLoaderStart: ({elementTagName}: LoaderStart) => void;
-  onLoadError: ({error, elementTagName}: LoadError) => void;
+  onLoaderStart?: ({elementTagName}: LoaderStart) => void;
+  onLoadError?: ({error, elementTagName}: LoadError) => void;
 };
 
 export const ConnectPayments = ({