I'm setting up with reference to README.md,
https://github.com/Shopify/better-html#how-to-use

but when I run the test with RSpec, the following error is displayed.

      ActionView::Template::Error:
        Invalid attribute name "class" does not match regular expression "/\\A[a-zA-Z0-9\\-\\:\\_]+\\z/"
        On line 1 column 5:
        <div class="container-fluid" id="wrapper_container">

I've tried several things with reference to the code in the gem's configuration file, but it doesn't work.
https://github.com/Shopify/better-html/blob/d2e117d6e6d375edfc25a664b1d04e1db7d4931f/lib/better_html/config.rb

When checking the operation of regular expressions using Rubular, my notation seems to work without problems.

I develop with Docker.
OS: mac, BigSur
Ruby: 2.7.7
Rails: 6.1.7
erb_lint: 0.3.1
better_html: 2.0.1

My code is here.

Gemfile

source 'https://rubygems.org'

git_source(:github) { |repo| "https://github.com/#{repo}.git" }

ruby '2.7.7'

group :development, :test do
  gem "better_html"
  gem 'erb_lint', require: false
end

config/initializers/better_html.rb

BetterHtml.config = BetterHtml::Config.new(YAML.load(File.read("#{Rails.root}/.better-html.yml")))

.better-html

---
allow_single_quoted_attributes: true
allow_unquoted_attributes: false
partial_attribute_name_pattern: /\A[a-zA-Z0-9\-\:\_]+\z/
# pending
# partial_tag_name_pattern: /\A[a-z0-9\-\:\_]+\z/

Please let me know why it doesn't work and how to fix it.
thank you.