Refactor Toggle to use Sass Modules

[tw15egan]

This issue is for updating the Toggle to Sass Modules in the @carbon/styles package. In this refactor, we will:

Copy over styles for for the component to packages/styles/scss/components/toggle/_toggle.scss
Any additional files will live in the folder packages/styles/scss/components/toggle/
Create an _index.scss at packages/styles/scss/components/toggle/_index.scss
Create a test file at packages/styles/scss/components/tests/toggle.js
Add storybook to packages/carbon-react
The _index.scss should:

@forward the mixin and any variables from _toggle.scss
Include the styles from _toggle.scss by calling the mixin
The toggle-test.js file should test the following:

The Public API of the toggle/_index.scss file
Any configuration options that are present for the file
The _toggle.scss will then need to be refactored to use the new import paths and conventions. You can find common recipes here: #8899