Increase benchmark warmup time

[ericywl]

Motivation/summary

Fixes #14948

Checklist

N / A

How to test these changes

Run throughput benchmark

[mergify]

This pull request does not have a backport label. Could you fix it @ericywl? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-7.17 is the label to automatically backport to the 7.17 branch.
• backport-8./d is the label to automatically backport to the 8./d branch. /d is the digit.
• backport-8.x is the label to automatically backport to the 8.x branch.

[mergify]

backport-8.x has been added to help with the transition to the new branch 8.x.
If you don't need it please use backport-skip label.

[ericywl]

@rubvs From what I can gather, the benchmark warmup time is configured by BENCHMARK_WARMUP_TIME. Let me know if I missed anything. I will try to run the benchmarks and verify.

[rubvs]

@ericywl Correct. This should be the only change to make. You can move this out-of-draft and let's get feedback from the rest of the team.

With this issue there isn't much "testing" you can do. I've already concluded this through running many benchmarks. However, this is a great first-issue:

• It'll force you to read and hopefully improve the docs, see workflow.md in Throughput.
• Trigger a benchmark in GitHub Actions that run on ESS.
• Trigger a benchmark from your local machine that runs in ESS.
• Spot the env var change in the Terraform provisioning logs for confirmation.