No underscore style (#42898)

Just like activestorage.js

actiontext/README.md

@@ -6,7 +6,7 @@ You can read more about Action Text in the [Action Text Overview](https://edgegu
 
 ## Development
 
-The JavaScript for Action Text is distributed both as a npm module under @rails/actiontext and via the asset pipeline as action_text.js (and we mirror Trix as trix.js). To ensure that the latter remains in sync, you must run `yarn build` and checkin the artifacts whenever the JavaScript source or the Trix dependency is bumped. CSS changes must be brought over manually to app/assets/stylesheets/trix.css
+The JavaScript for Action Text is distributed both as a npm module under @rails/actiontext and via the asset pipeline as actiontext.js (and we mirror Trix as trix.js). To ensure that the latter remains in sync, you must run `yarn build` and checkin the artifacts whenever the JavaScript source or the Trix dependency is bumped. CSS changes must be brought over manually to app/assets/stylesheets/trix.css
 
 ## License
 

actiontext/lib/action_text/engine.rb

@@ -28,7 +28,7 @@ module ActionText
 
     initializer "action_text.asset" do
       if Rails.application.config.respond_to?(:assets)
-        Rails.application.config.assets.precompile += %w( action_text trix )
+        Rails.application.config.assets.precompile += %w( actiontext.js trix.js trix.css )
       end
     end
 

actiontext/lib/generators/action_text/install/install_generator.rb

@@ -45,12 +45,12 @@ module ActionText
           end
         else
           if (application_layout_path = Rails.root.join("app/views/layouts/application.html.erb")).exist?
-            insert_into_file application_layout_path.to_s, %(\n    <%= javascript_include_tag "trix", "action_text", "data-turbo-track": "reload", defer: true %>), before: /\s*<\/head>/
+            insert_into_file application_layout_path.to_s, %(\n    <%= javascript_include_tag "trix", "actiontext", "data-turbo-track": "reload", defer: true %>), before: /\s*<\/head>/
           else
             say <<~INSTRUCTIONS, :green
-              You must add the action_text.js and trix.js JavaScript files to the head of your application layout:
+              You must add the actiontext.js and trix.js JavaScript files to the head of your application layout:
 
-              <%= javascript_include_tag "trix", "action_text", "data-turbo-track": "reload", defer: true %>
+              <%= javascript_include_tag "trix", "actiontext", "data-turbo-track": "reload", defer: true %>
             INSTRUCTIONS
           end
         end

actiontext/rollup.config.js

@@ -5,7 +5,7 @@ export default [
   {
     input: "app/javascript/actiontext/index.js",
     output: {
-      file: "app/assets/javascripts/action_text.js",
+      file: "app/assets/javascripts/actiontext.js",
       format: "es"
     },
     plugins: [