test_require.rb: ignore EPERM at UNC
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59009 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
test_require.rb: ignore EPERM at UNC
GetFileAttributes and CreateFile with backup semantics fail at a
symlink in a shared folder to another shared folder.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59009 b2dd03c8-39d4-4d8f-98ff-823fe69b080e