feat(divider): align component with fusion DS

[ibutakova]

Proposed behaviour

Use fusion design tokens for styling Divider

Current behaviour

Styling is not aligned with design tokens

Checklist

• Commits follow our style guide
• Related issues linked in commit messages if required
• Screenshots are included in the PR if useful
• All themes are supported if required
• Unit tests added or updated if required
• Playwright automation tests added or updated if required
• Storybook added or updated if required
• Translations added or updated (including creating or amending translation keys table in storybook) if required
• Typescript d.ts file added or updated if required
• Related docs have been updated if required

QA

• Tested in provided StackBlitz sandbox/Storybook
• Add new Playwright test coverage if required
• Carbon implementation matches Design System/designs
• UI Tests GitHub check reviewed if required

Additional context

Testing instructions

[tomdavies73]

suggestion: I'm not sure additional unit tests are needed here, some changes are valid if we're updating existing tests to use the new tokens.

If we don't need a test for coverage here we can probably avoid adding new ones, chromatic should be doing the majority of our styling checks via snapshots

[ibutakova]

Thanks. Shared colorMap is covered by vertical tests, so I removed three tests not to duplicate. Others look ok.