fix encoding spec

"UTF-8" is invalid encoding name in Emacs, use "utf-8" instead.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46948 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/erb.rb

@@ -68,7 +68,7 @@ require "cgi/util"
 # a magic comment, however, it returns a string in the encoding specified
 # by the magic comment.
 #
-#   # -*- coding: UTF-8 -*-
+#   # -*- coding: utf-8 -*-
 #   require 'erb'
 #
 #   template = ERB.new <<EOF

test/erb/test_erb_m17n.rb

@@ -1,4 +1,4 @@
-# -*- coding: UTF-8 -*-
+# -*- coding: utf-8 -*-
 require 'test/unit'
 require 'erb'
 

test/psych/test_yamldbm.rb

@@ -1,5 +1,3 @@
-# -*- coding: UTF-8 -*-
-
 require_relative 'helper'
 require 'tmpdir'
 

test/rubygems/test_gem_specification.rb

@@ -1,4 +1,3 @@
-# -*- coding: UTF-8 -*-
 require 'rubygems/test_case'
 require 'pathname'
 require 'stringio'