- set class to is-disabled when loading
- clean up classes logic

Co-authored-by: @danmh <dmizzi-harris@gitlab.com>

feat(toggle): use design tokens for is-disabled colors and clean up styling

Closes #2924

See merge request gitlab-org/gitlab-ui!4677



Merged-by: Vanessa Otto <votto@gitlab.com>
Approved-by: Dan MH <dmizzi-harris@gitlab.com>
Approved-by: Vanessa Otto <votto@gitlab.com>
Co-authored-by: sdejonge <sdejonge@gitlab.com>
Co-authored-by: James Rushford <jrushford@gitlab.com>

# [96.1.0](gitlab-org/gitlab-ui@v96.0.0...v96.1.0) (2024-10-10)

### Features

* **GlToggle:** pairing with James feedback ([f261031f](gitlab-org/gitlab-ui@f261031f))
* **toggle:** adds specificity for when is-checked and is-disabled ([9fd0dafa](gitlab-org/gitlab-ui@9fd0dafa))
* **toggle:** another clean up of css states ([77a66724](gitlab-org/gitlab-ui@77a66724))
* **toggle:** apply suggestions ([fd2e809c](gitlab-org/gitlab-ui@fd2e809c))
* **toggle:** fix linting error ([2218423b](gitlab-org/gitlab-ui@2218423b))
* **toggle:** further cleanup of CSS ([b278a9e7](gitlab-org/gitlab-ui@b278a9e7))
* **toggle:** make no pointer events on toggle icon ([ac7c1f43](gitlab-org/gitlab-ui@ac7c1f43))
* **toggle:** rearrange css order for specificity ([589e39e9](gitlab-org/gitlab-ui@589e39e9))
* **toggle:** set class to is-disabled when loading ([478f2fb9](gitlab-org/gitlab-ui@478f2fb9))
* **toggle:** use design tokens for is-disabled colors and clean up styling ([fad38fa3](gitlab-org/gitlab-ui@fad38fa3))