net/http/header.rb: remove a hack
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42403 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
net/http/header.rb: remove a hack
for the bug fixed at [Bug #8739].
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42403 b2dd03c8-39d4-4d8f-98ff-823fe69b080e