Migrate Performance Metrics to Buildkite pipeline

[wojtekn]

Related issues

• Fixes STU-978

Proposed Changes

• I propose migrating Performance Metrics tests from GitHub action to Buildkite.

Testing Instructions

• Confirm that the build goes through
• Confirm there is a performance metrics comment under the PR

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[wpmobilebot]

📊 Performance Test Results

Comparing 716b93a vs trunk

site-editor

Metric	trunk	716b93a	Diff	Change
load	7235.00 ms	5502.00 ms	-1733.00 ms	🟢 -24.0%

site-startup

Metric	trunk	716b93a	Diff	Change
siteCreation	9101.00 ms	9105.00 ms	+4.00 ms	🔴 0.0%
siteStartup	3949.00 ms	3956.00 ms	+7.00 ms	🔴 0.2%

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Results are median values from multiple test runs.

Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change

[mokagio]

Have you considered running this check at the start of the script? This way, if the "skip" branch of the conditional should run, we can avoid installing dependencies and the rest of the setup and save some time.

[mokagio]

Took a stab in #2327

[wojtekn]

Would it make sense to run this condition as part of pipeline logic, as we do in other steps? For example:

if: build.branch == 'trunk' || build.pull_request.base_branch == 'trunk'

[mokagio]

Sounds good @wojtekn .

I see 716b93a implements this and also adds the additional condition of the PR having to be ready for review. Neat.

Ship it!

[mokagio]

Nitpick: I think calling bash is redundant here because the script already has !#/usr/bin/env bash. Most of the .sh scripts we use as the command steps in other projects are invoked that way.

Suggested change

	command: bash .buildkite/commands/run-metrics-tests.sh
	command: .buildkite/commands/run-metrics-tests.sh

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Update: After looking at the pipeline while working on #2327, I noticed that calling the script via bash is the standard in the pipeline, so it'd be out of place to change it in this PR.

[wojtekn]

Thanks for confirming that.