Remove modularize script (#21587)

Author: marcofugaro

.github/CONTRIBUTING.md

@@ -5,15 +5,15 @@ It is assumed that you know a little about node.js and git. If not, [here's some
 
 * Install [Node.js](https://nodejs.org/)
 * Install [Git](https://git-scm.com/)
-* [Fork](https://help.github.com/en/github/getting-started-with-github/fork-a-repo) three.js 
+* [Fork](https://help.github.com/en/github/getting-started-with-github/fork-a-repo) three.js
 * Open your OS’s terminal
 * Change into the directory you’d like
 * Clone your forked repo
 
       git clone https://github.com/[yourgithubname]/three.js.git
 
 * Go into the three.js directory.
-        
+
       cd ./three.js
 
 * Install the dependencies
@@ -39,20 +39,20 @@ Many linting errors can be fixed automatically by running
     npm lint-fix
 
 If you’d like to make a minified version of the build files i.e. ‘build/three.min.js’ run:
-        
+
     npm run build
 
 ## Making changes
 
 When you’ve decided to make changes, start with the following:
 
 * Update your local repo
-        
+
       git pull https://github.com/mrdoob/three.js.git
       git push
 
 * Make a new branch from the dev branch
-        
+
       git checkout dev
       git branch [mychangesbranch]
       git checkout [mychangesbranch]
@@ -70,8 +70,8 @@ When you’ve decided to make changes, start with the following:
 * If you modify existing code, run relevant examples to check they didn't break and there wasn't performance regress.
 * If you add some assets for the examples (models, textures, sounds, etc), make sure they have a proper license allowing for their use here, less restrictive the better. It is unlikely for large assets to be accepted.
 * If some issue is relevant to patch / feature, please mention it with hash (e.g. #2774) in a commit message to get cross-reference in GitHub.
-* If you modify files in `examples/js` directory, then don't perform any changes in the `examples/jsm`, JavaScript modules are auto-generated via running `node utils/modularize.js`.
-* If end-to-end test failed in Travis and you are sure that all is correct, make a new screenshots with 
+* If you modify files in `examples/jsm` directory, then don't perform any changes in the `examples/js`, non-module files are auto-generated by running `npm run build-examples`.
+* If end-to-end test failed in Travis and you are sure that all is correct, make a new screenshots with
 
       npm run make-screenshot <example_1_name> ...<example_N_name>