Remove temporary report file

[chris-rock]

Cookbook version

2.0.0

Scenario:

Previously we used the runner with generating a json file: https://github.com/chef-cookbooks/audit/blob/v1.1.0/resources/profile.rb#L121-L135 (edited)

output = quiet ? ::File::NULL : $stdout
runner = ::Inspec::Runner.new('report' => true, 'format' => formatter, 'output' => output)
report = runner.report.to_json

This helps us to remove https://github.com/chef-cookbooks/audit/blob/master/files/default/audit_report.rb#L86-L87 and https://github.com/chef-cookbooks/audit/blob/master/libraries/helper.rb#L74-L80. For users who require a local json report, we should implement #126