Ruby » Ruby master

merge revision(s) 57530: [Backport #13191]

    sample/pty/shl.rb: update sample

    * Specify frozen_string_literal: true.
    * Fix TypeError of raise.
    * Use a character literal instead of Integer.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@59228 b2dd03c8-39d4-4d8f-98ff-823fe69b080e