ci: migrate to tenki runners

[asutosh23]

PR: Migrate CI Workflows to Tenki Runners

About Tenki

Tenki provides high-performance, flexible GitHub Runners that replace self-hosted or legacy CI solutions with a faster, more secure, and cost-efficient alternative.

With Tenki, teams benefit from:

• ⚡ Faster pipelines: ~30% average improvement in job execution time through optimized infrastructure
• 💰 Significant savings: up to ~90% cheaper compared to traditional CI runner solutions
• 🔒 Stronger security: runners run on ephemeral VMs, ensuring clean, isolated environments for every job
• 📈 Scalable options: a broad catalog of runner types with built-in autoscaling to match workload demand

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Modifications in This PR

• Updated GitHub Actions workflows to use Tenki runner labels

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✅ This PR completes the initial migration to Tenki runners.

[eyusufatik]

Hey there, thanks for the PR!

Can we test the coverage CI first instead of build-and-push? I think it'd be a better benchmark.