Don't fast-track large block submissions

[metachris]

📝 Summary

Large block submissions (i.e. with transactions from L2 rollups) are severely impacting block submission and simulation latency.

This change will not fast-track payloads above a certain size (230kb by default).

⛱ Motivation and Context

This chart shows how all slow fast-tracked submissions are due to large payloads:

Even in high-priority, the submissions will still get accepted, but without blocking fast-tracked ones from succeeding quickly.

⚡ Impact

After deploying this change, the average fast-track submission time is <200ms:

Last 48h:

Last 3h:

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✅ I have run these commands

• make lint
• make test-race
• go mod tidy
• I have seen and agree to CONTRIBUTING.md