Couple more undoc APIs from .NET 9

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Learn Build status updates of commit 7612dbc:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
xml/System.Diagnostics/DebuggerDisableUserUnhandledExceptionsAttribute.xml	:white_check_mark:Succeeded	View
xml/System.IO/File.xml	:white_check_mark:Succeeded	View

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