specify 'bytes' encoding in dist.ini

[stuart-little]

This is meant to address the issue noted here: newer Dist::Zilla versions will choke on binary files (like xt/primes1.zip) unless a binary "encoding" is specified to override the UTF-8 default.

Without the patch, running dzil build in the cloned repo produces complaints like this:

Could not decode UTF-8 xt/primes1.zip; filename set by GatherDir (Dist::Zilla::Plugin::GatherDir line 226); encoded_content added by @Basic/GatherDir (Dist::Zilla::Plugin::GatherDir line 227); error was: UTF-8 "\x8C" does not map to Unicode at /root/.perlbrew/libs/perl-5.35.0@535/lib/perl5/Dist/Zilla/Role/File.pm line 145.