Add cryptography PlatformNotSupportedExceptions

[gewarren]

Contributes to dotnet/docs#28861
Contributes to dotnet/docs#28834
Contributes to dotnet/docs#28812

[ghost]

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Issue Details

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Contributes to dotnet/docs#28861
Contributes to dotnet/docs#28834
Contributes to dotnet/docs#28812

Author:	gewarren
Assignees:	-
Labels:	area-System.Security
Milestone:	-

[opbld32]

Docs Build status updates of commit 8b7991f:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Security.Cryptography/ECDiffieHellmanCng.xml	✅Succeeded	View
xml/System.Security.Cryptography/ECDiffieHellmanCngPublicKey.xml	✅Succeeded	View
xml/System.Security.Cryptography/ECDiffieHellmanPublicKey.xml	✅Succeeded	View

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

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