[lec02] update option.scala

src/main/scala/errors/Option.scala

 package errors
 
 sealed trait Option[+A] {
-  def map[B](f: A => B): Option[B] = this match {
-    case None => None
-    case Some(a) => Some(f(a))
-  }
+  def map[B](f: A => B): Option[B] = ???
 
   def getOrElse[B >: A](default: => B): B = ???