Port System.Security.Cryptography docs for .NET 9

[vcsjones]

Port missing documentation for System.Security.Cryptography for .NET 9.

/cc @gewarren @carlossanlop @bartonjs

I made some minor tweaks to the documentation while porting for correctness and a missing exception.

Closes dotnet/runtime#106790

[learn-build-service-prod]

Learn Build status updates of commit 7e2b999:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Security.Cryptography/CngKeyCreationOptions.xml	✅Succeeded	View
xml/System.Security.Cryptography/SafeEvpPKeyHandle.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel

[learn-build-service-prod]

Learn Build status updates of commit 0fd356f:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Security.Cryptography/CngKeyCreationOptions.xml	✅Succeeded	View
xml/System.Security.Cryptography/SafeEvpPKeyHandle.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel