Add Docswell to allowing embed script/iframe list

[ku-suke]

What

This is a request to add docswell.com to the list of embed whitelist (JS/iframe).

https://www.docswell.com/

Rspec test result

~
      with HTML embed code for Docswell
        forces async attribute on script
        with scheme
          forces width attribute on iframe
        without scheme
          forces width attribute on iframe
~
Finished in 1.33 seconds (files took 1.81 seconds to load)
526 examples, 0 failures

Note: .rubocop_todo.yml is not included in this PR.

[ku-suke]

Yes, but this error caused without generating .rubocop_todo.yml. This error will be fixed after rubocop --auto-gen-config --exclude-limit 99999. You can generate before merge, or can I commit the generated file?

[getty104]

@ku-suke The bundle exec rake style:auto_correct command corrects lint errors. Can you try to run the command ?

[ku-suke]

Sorry, I understand, added frozen_string_literal: true instead excluding in .rubocop_todo.yml.