update react typings, React.ReactChildren was wrong

Author: dreamsoft07

README.md

@@ -467,8 +467,10 @@ Notice we have used the TSDoc `/** comment */` style here on each prop. You can
 export declare interface AppProps {
   children1: JSX.Element; // bad, doesnt account for arrays
   children2: JSX.Element | JSX.Element[]; // meh, doesnt accept functions
-  children3: React.ReactChild | React.ReactChildren; // better, but doesnt accept strings
+  children3: React.ReactChildren; // despite the name, not at all an appropriate type; it is a utility
+  children3: React.ReactChild[]; // better
   children: React.ReactNode; // best, accepts everything
+  functionChildren: (name: string) => React.ReactNode; // recommended function as a child render prop type
   style?: React.CSSProperties; // to pass through style props
   onChange?: React.FormEventHandler<HTMLInputElement>; // form events! the generic parameter is the type of event.target
   props: Props & React.PropsWithoutRef<JSX.IntrinsicElements['button']>; // to impersonate all the props of a button element without its ref