Test the Quill JS presence and version

spec/system/quill_js_spec.rb

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+RSpec.describe 'Quill JS', type: :system do
+  it 'has a Javascript function defined and returns the version', :aggregate_failures do
+    visit '/admin/posts'
+
+    expect(page.evaluate_script('typeof Quill')).to eq 'function'
+    expect(page.evaluate_script('Quill.version')).to eq(ActiveAdmin::QuillEditor::QUILL_VERSION)
+  end
+end