fix(OnyxNavBar): align horizontal padding with grid

[larsrickert]

closes #1279

• align nav bar horizontal padding with grid

Checklist

• [x] If a new component is added, at least one Playwright screenshot test is added
• [x] A changeset is added with npx changeset add if your changes should be released as npm package (because they affect the library usage)

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 2f3f6c9a53e9bb82d04e0f850bcb617787b0589b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 7 packages

| Name | Type | | ------------------------- | ----- | | sit-onyx | Patch | | alpha-test-app | Patch | | playground | Patch | | @sit-onyx/chartjs-plugin | Patch | | @sit-onyx/nuxt | Patch | | @sit-onyx/storybook-utils | Patch | | @sit-onyx/vitepress-theme | Patch |

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