Fix encoding parameter in example

[sdwheeler]

PR Summary

Fix encoding parameter in example. PlatyPS expects the enum instead of a string.

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[opbld30]

Docs Build status updates of commit 0824288:

✅ Validation status: passed

File	Status	Preview URL	Details
reference/docs-conceptual/dev-cross-plat/create-help-using-platyps.md	✅Succeeded	View (>=powershell-5.1)

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[michaeltlombardi]

LGTM!