ci: update SDK harness to 0.9.0

[marandaneto]

💡 Motivation and Context

Update this SDK's compliance setup to use posthog-sdk-test-harness 0.9.0. The reusable workflow is pinned to the 0.9.0 release commit SHA (
68498bcf3ae95ac941476e6ca3d42d6086e1c7fd) instead of a tag, while the harness Docker image uses the published 0.9.0 image tag.

💚 How did you test it?

• Confirmed the PR branch has no remaining references to the previous harness workflow SHA or 0.8.0 harness image/version.
• Parsed changed GitHub Actions workflow YAML locally where workflow files changed.

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• I updated the docs if needed.
• No breaking change or entry added to the changelog.

If releasing new changes

• Ran sampo add to generate a changeset file

🤖 Agent context

Autonomy: Human-driven (agent-assisted)

Updated SDK compliance harness references only. Kept the change limited to workflow, Docker Compose, and local compliance docs where those references existed.

[greptile-apps]

_{Reviews (1): Last reviewed commit: "ci: update SDK harness to 0.9.0" | Re-trigger Greptile}

[github-actions]

posthog-python Compliance Report

Date: 2026-06-30 10:37:31 UTC
Duration: 176171ms

✅ All Tests Passed!

45/45 tests passed

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Capture Tests

✅ 29/29 tests passed

View Details

Test	Status	Duration
Format Validation.Event Has Required Fields	✅	517ms
Format Validation.Event Has Uuid	✅	1506ms
Format Validation.Event Has Lib Properties	✅	1507ms
Format Validation.Distinct Id Is String	✅	1506ms
Format Validation.Token Is Present	✅	1507ms
Format Validation.Custom Properties Preserved	✅	1506ms
Format Validation.Event Has Timestamp	✅	1507ms
Retry Behavior.Retries On 503	✅	9513ms
Retry Behavior.Does Not Retry On 400	✅	3510ms
Retry Behavior.Does Not Retry On 401	✅	3507ms
Retry Behavior.Respects Retry After Header	✅	9513ms
Retry Behavior.Implements Backoff	✅	23527ms
Retry Behavior.Retries On 500	✅	7504ms
Retry Behavior.Retries On 502	✅	7513ms
Retry Behavior.Retries On 504	✅	7509ms
Retry Behavior.Max Retries Respected	✅	23529ms
Deduplication.Generates Unique Uuids	✅	1497ms
Deduplication.Preserves Uuid On Retry	✅	7515ms
Deduplication.Preserves Uuid And Timestamp On Retry	✅	14512ms
Deduplication.Preserves Uuid And Timestamp On Batch Retry	✅	7515ms
Deduplication.No Duplicate Events In Batch	✅	1504ms
Deduplication.Different Events Have Different Uuids	✅	1506ms
Compression.Sends Gzip When Enabled	✅	1507ms
Batch Format.Uses Proper Batch Structure	✅	1507ms
Batch Format.Flush With No Events Sends Nothing	✅	1005ms
Batch Format.Multiple Events Batched Together	✅	1505ms
Error Handling.Does Not Retry On 403	✅	3509ms
Error Handling.Does Not Retry On 413	✅	3506ms
Error Handling.Retries On 408	✅	7514ms

Feature_Flags Tests

✅ 16/16 tests passed

View Details

Test	Status	Duration
Request Payload.Request With Person Properties Device Id	✅	1003ms
Request Payload.Flags Request Uses V2 Query Param	✅	1006ms
Request Payload.Flags Request Hits Flags Path Not Decide	✅	1006ms
Request Payload.Flags Request Omits Authorization Header	✅	1007ms
Request Payload.Token In Flags Body Matches Init	✅	1006ms
Request Payload.Groups Round Trip	✅	1006ms
Request Payload.Groups Default To Empty Object	✅	1006ms
Request Payload.Person Properties Distinct Id Auto Populated When Caller Omits It	✅	1007ms
Request Payload.Disable Geoip False Propagates As Geoip Disable False	✅	1006ms
Request Payload.Disable Geoip Omitted Defaults To False	✅	1006ms
Request Payload.Flag Keys To Evaluate Contains Only Requested Key	✅	1006ms
Request Lifecycle.No Flags Request On Init Alone	✅	502ms
Request Lifecycle.No Flags Request On Normal Capture	✅	1507ms
Request Lifecycle.Two Flag Calls Produce Two Remote Requests	✅	1010ms
Request Lifecycle.Mock Response Value Is Returned To Caller	✅	1002ms
Side Effect Events.Get Feature Flag Captures Feature Flag Called Event	✅	1509ms