Fix WorkflowStepCompletedRequest options handling

[CedricFinance]

This PR fixes handling for options of WorkflowStepCompletedRequest. (description added by @kanata2)

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Pull Request Guidelines

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They are strictly guidelines to help manage expectations.

PR preparation

Run make pr-prep from the root of the repository to run formatting, linting and tests.

Should this be an issue instead

• is it a convenience method? (no new functionality, streamlines some use case)
• exposes a previously private type, const, method, etc.
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[kanata2]

Thanks!