chore: add comet opik to vendors.yaml

[vincentkoc]

• I have read and followed the Contributing docs, especially the "First-time contributing?" section.
• This PR has content that I did not fully write myself.
• I used AI and I have read and followed the Generative AI Contribution Policy.
• I have the experience and knowledge necessary to understand, review, and validate all content in this PR.¹

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Comet Opik is an open-source and commercial vendor that natively supports opentelemetry, adding an entry onto vendors.yaml

Footnotes

1. Yes, I can answer maintainer questions about the content of this PR, without using AI. ↩

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: vincentkoc / name: Vincent Koc (fe80a1a)