t/04e_file.t fails randomly

[brummett]

We always seem to get at least one failure of this test on CPAN testers after every release:
http://www.cpantesters.org/cpan/report/ab048eb2-83c6-11e6-ab41-c893a58a4b8c
http://www.cpantesters.org/cpan/report/48c61a2e-8298-11e6-ab41-c893a58a4b8c