Provide aos.js localy to not violate GDPR

Another patch with another way to do this with

# scroll_effects
plugin.scroll_effects.build:
  dependencies:
    - aos.remote

# AOS remote library.
aos.remote:
  remote: https://michalsnik.github.io/aos
  version: 1.x
  license:
    name: MIT
    url: https://github.com/michalsnik/aos/blob/master/LICENSE
    gpl-compatible: true
  js:
    https://unpkg.com/aos@2.3.1/dist/aos.js: { type: external, weight: -3, minified: true }
    js/plugins/scroll_effects/build.js: { }
  css:
    theme:
      https://unpkg.com/aos@2.3.1/dist/aos.css: { }

# AOS local library.
aos.local:
  js:
    /libraries/aos/dist/aos.js: { weight: -3, minified: true }
    js/plugins/scroll_effects/build.js: { }
  css:
    theme:
      /libraries/aos/dist/aos.css: { minified: true }

Switch to local when having the /libraries/aos/dist/aos.js in the PROJECT_PATH/libraries folder
A new config settings option will work for sure. not to keep using file_exists .. it could be a bootstrap_styling.setting value to use aos.remote or aos.local library