removes rubocop from dangerfile for now (#6168)

This will be re-enabled once I can reproduce and fix errors using travis local docker build.

Dangerfile

@@ -1,33 +1,7 @@
-require 'json'
-require 'shellwords'
-
 if git.lines_of_code > 500
   warn("This PR seems big, we prefer smaller PR. Please be sure this is needed and can't be split in smaller PRs.")
 end
 
-to_lint = git.modified_files + git.added_files
-files_to_lint = Shellwords.join(to_lint)
-rubocop_output = `bundle exec rubocop -f json --parallel #{files_to_lint}`
-if !rubocop_output.empty?
-  offenses = JSON.parse(rubocop_output)['files']
-    .select { |f| f['offenses'].any? }
-
-  def format_offense(offense)
-    output = "file: #{offense['path']}\n"
-    offense['offenses'].each do |o|
-      output << "#{o['message']} (line:#{o['location']['start_line']}, col:#{o['location']['start_column']})\n"
-    end
-    output << "\n"
-  end
-
-  if !offenses.empty?
-    fail(%{
-This PR has multiple rubocop offenses. We recommend configuring prettier linting in your editor:\n
-#{offenses.map { |o| format_offense(o) }.join('\n') }
-    })
-  end
-end
-
 prettier_offenses = `prettier --list-different "app/assets/stylesheets/**/*.scss" "app/assets/javascripts/**/*.es6" "test/javascripts/**/*.es6"`.split('\n')
 if !prettier_offenses.empty?
   fail(%{