Authentication example is useless

[the-jedi-code]

Need to show how to obtain the adminKey and not assume that it's already known.

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Document Details

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• ID: 5c0b7e33-385a-9a6f-b023-4ca120ec8406
• Version Independent ID: 7c8235b3-1cfb-4f57-8695-0406809a4ea5
• Content: Smart cards - UWP applications
• Content Source: windows-apps-src/security/smart-cards.md
• Product: uwp
• Technology: platform
• GitHub Login: @hickeys
• Microsoft Alias: hickeys

[the-jedi-code]

bool verifyResult = false;
SmartCard card = await rootPage.GetSmartCard();
SmartCardProvisioning provisioning =
    await SmartCardProvisioning.FromSmartCardAsync(card);

using (SmartCardChallengeContext context =
       await provisioning.GetChallengeContextAsync())
{
    IBuffer response = ChallengeResponseAlgorithm.CalculateResponse(
        context.Challenge,
        rootPage.AdminKey);

    verifyResult = await context.VerifyResponseAsync(response);
}