test_fileutils.rb: fix relative symlink path
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57647 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
test_fileutils.rb: fix relative symlink path
symlink path, the target should be relative to the directory in
which the symlink gets created.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57647 b2dd03c8-39d4-4d8f-98ff-823fe69b080e