Gem::Commands::PushCommand#get_attestations_part

# File tmp/rubies/ruby-3.4.1/lib/rubygems/commands/push_command.rb, line 124
def get_attestations_part
  bundles = "[" + options[:attestations].map do |attestation|
    Gem.read_binary(attestation)
  end.join(",") + "]"
  [
    "attestations",
    bundles,
    { content_type: "application/json" },
  ]
end