Fix grammar (#295)

Co-authored-by: lazypassion <25536767+lazypassion@users.noreply.github.com>

read.go

@@ -16,7 +16,7 @@ import (
 	"nhooyr.io/websocket/internal/xsync"
 )
 
-// Reader reads from the connection until until there is a WebSocket
+// Reader reads from the connection until there is a WebSocket
 // data message to be read. It will handle ping, pong and close frames as appropriate.
 //
 // It returns the type of the message and an io.Reader to read it.