This mirrors what we have for the other actions. Used by createStatusReportBase. I considered changing getRequiredInput("matrix") to getOptionalInput("matrix") there (and think that makes sense as a change), but thought it would be useful to have the matrix value in the start-proxy telemetry as well if it is available.

Risk assessment

For internal use only. Please select the risk level of this change:

• Low risk: Changes are fully under feature flags, or have been fully tested and validated in pre-production environments and are highly observable, or are documentation or test only.

Merge / deployment checklist

• Confirm this change is backwards compatible with existing workflows.
• Consider adding a changelog entry for this change.
• Confirm the readme and docs have been updated if necessary.