chore: swap dependabot for renovate

[castastrophe]

Description

Renovate offers a nice dependency dashboard and supports the same features as dependabot. After team discussion, this migrates us off dependabot and replaces the settings and groupings with their renovate equivalence.

To-do list

• I have read the contribution guidelines.
• [n/a] I have updated relevant storybook stories and templates.
• [n/a] I have tested these changes in Windows High Contrast mode.
• [n/a] If my change impacts other components, I have tested to make sure they don't break.
• If my change impacts documentation, I have updated the documentation accordingly.
• ✨ This pull request is ready to merge. ✨

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Latest commit: 5db769d

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[github-actions]

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Summary

Total size: 2.25 MB^*

🎉 No changes detected in any packages

* Size is the sum of all main files for packages in the library.
* An ASCII character in UTF-8 is 8 bits or 1 byte.

[github-actions]

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