Adding the dark mode version of graphic

[Kersten Richter (kersten1)]

No description provided.

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⚠️ DCO CHECK FAILED ⚠️

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[github-actions]

⚠️ DCO CHECK FAILED ⚠️

The Developer's Certificate of Origin (DCO) check has failed for this pull request.
To fix this, you need to sign off on your commits.

For instructions on how to set up signed commits, please see:
https://github.com/riscv/docs-resources/blob/2aef34ec803cf3475376172bac78a35d5801cb21/CONTRIBUTING.md

Once you have signed your commits, you will need to force-push your changes.