Describe the bug

Currently, the PushNotificationManager APIs return E_FAIL if SelfContained scenario is not supported. A better HRESULT to use would be HRESULT_FROM_WIN32(ERROR_NOT_SUPPORTED).

From this conversation:
#2389 (comment)

Steps to reproduce the bug

In unpackaged/SelfContained environment, call into PushNotificationManager APIs and view the returned error code.

Expected behavior

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Screenshots

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NuGet package version

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Packaging type

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Windows version

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IDE

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Additional context

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