doc: fix typo in stream.md · nodejs/node@dcdc905

Original file line number	Diff line number	Diff line change
`@@ -1922,7 +1922,7 @@ user programs.`
`1922`	`1922`
`1923`	`1923`	`transform._transform()` is never called in parallel; streams implement a
`1924`	`1924`	queue mechanism, and to receive the next chunk, `callback` must be
`1925`		`-called, either synchronously or asychronously.`
	`1925`	`+called, either synchronously or asynchronously.`
`1926`	`1926`
`1927`	`1927`	`#### Class: stream.PassThrough`
`1928`	`1928`