[BUG]: WorkflowConclusionStatus missing startup_failure

[matthewdevenny]

What happened?

According to the web hook documentation for a workflow_run completed event, startup_failure is also valid conclusion

https://docs.github.com/en/webhooks/webhook-events-and-payloads?actionType=completed#workflow_run

Versions

octokit/dotnet-sdk:v0.0.31, .NET 8

Code of Conduct

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[github-actions]

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