theme generator: Mixed line endings in generated example_theme.libraries.yml

Problem/Motivation

Generated example_theme.libraries.yml contains CRLF

Example:

#     - example_theme/clearfix
#     - example_theme/visually-hidden
^M
body-text:
  css:
    component:
      dist/css/body-text.css: {}
^M
button:
  css:
    component:
      dist/css/button.css: {}
^M

See:

grep -inr '\\r\\n' ./theme_generator_9
./theme_generator_9/generators/component/index.js:163:      '\r\n'
./theme_generator_9/generators/starter-kit/index.js:365:                  separator: '\r\n'
./theme_generator_9/generators/starter-kit/index.js:375:                '\r\n'