Fix typo

[gewarren]

Fixes https://github.com/dotnet/dotnet-api-docs/issues/10364

[learn-build-service-prod[bot]]

Learn Build status updates of commit 449765b:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
xml/System.Windows.Forms/Control.xml	:white_check_mark:Succeeded	View

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