Fix sample code

Mitsuru Kanenobu · Mitsuru Kanenobu · commit 169b812f6425 · 2020-06-07T19:07:27.000+09:00
diff --git a/_ja/tour/singleton-objects.md b/_ja/tour/singleton-objects.md
@@ -102,7 +102,7 @@ scalaCenterEmail match {
     s"""Registered an email
        |Username: ${email.username}
        |Domain name: ${email.domainName}
-     """)
+     """.stripMargin)
   case None => println("Error: could not parse email")
 }
 ```

Original file line number	Diff line number	Diff line change
`@@ -102,7 +102,7 @@ scalaCenterEmail match {`
`102`	`102`	`s"""Registered an email`
`103`	`103`	`\|Username: ${email.username}`
`104`	`104`	`\|Domain name: ${email.domainName}`
`105`		`- """)`
	`105`	`+ """.stripMargin)`
`106`	`106`	`case None => println("Error: could not parse email")`
`107`	`107`	`}`
`108`	`108`	```