doc: add readline.emitKeypressEvents note

doc: add readline.emitKeypressEvents note · nodejs/node@594e3c2

Original file line number	Diff line number	Diff line change
`@@ -452,6 +452,10 @@ autocompletion is disabled when copy-pasted input is detected.`
`452`	`452`
`453`	`453`	If the `stream` is a [TTY][], then it must be in raw mode.
`454`	`454`
	`455`	+Note: This is automatically called by any readline instance on its `input`
	`456`	+if the `input` is a terminal. Closing the `readline` instance does not stop
	`457`	+the `input` from emitting `'keypress'` events.
	`458`	`+`
`455`	`459`	```js
`456`	`460`	`readline.emitKeypressEvents(process.stdin);`
`457`	`461`	`if (process.stdin.isTTY)`