indent to backticks

convert_to_backticks.rb

Dir.glob('content/**/*.md') do |file|
  content = File.read(file)
  content = content.gsub(/{:.terminal}\n[\s\S]*?^$/) do |match|
    lines = match.lines

    lines = lines[1..-1].map do |line|
      line[4..-1]
    end
    lines.unshift("``` command-line\n")
    lines << "```\n"

    lines.join
  end

  File.write(file, content)
end