Update Assembly.IsFullyTrusted and AppDomain.IsFullyTrusted properties for .NET Core/5+ behaviour

[elinor-fung]

Summary

Assembly.IsFullyTrusted and AppDomain.IsFullyTrusted properties return set values in .NET Core/5+. Make the docs call that out.

cc @dotnet/appmodel @jkotas

[learn-build-service-prod]

Learn Build status updates of commit 435c2d1:

❌ Validation status: errors

Please follow instructions here which may help to resolve issue.

File	Status	Preview URL	Details
	❌Error		Details
xml/System.Reflection/Assembly.xml	❌Error		Details

• Line 0, Column 0: [Error: ECMA2Yaml_File_LoadFailed] Failed to load 1 files, aborting...

xml/System.Reflection/Assembly.xml

• Line 0, Column 0: [Error: ECMA2Yaml_InternalError]

Intenal Several Error: System.Xml.XmlException: The 'Docs' start tag on line 3905 position 8 does not match the end tag of 'value'. Line 3911, position 11.
   at System.Xml.XmlTextReaderImpl.Throw(Exception e)
   at System.Xml.XmlTextReaderImpl.Throw(String res, String[] args)
   at System.Xml.XmlTextReaderImpl.ThrowTagMismatch(NodeData startTag)
   at System.Xml.XmlTextReaderImpl.ParseEndElement()
   at System.Xml.XmlTextReaderImpl.ParseElementContent()
   at System.Xml.Linq.XContainer.ReadContentFrom(XmlReader r)
   at System.Xml.Linq.XDocument.Load(XmlReader reader, LoadOptions options)
   at System.Xml.Linq.XDocument.Parse(String text, LoadOptions options)
   at ECMA2Yaml.ECMALoader.LoadType(FileItem typeFile)
   at ECMA2Yaml.ECMALoader.LoadTypes(String basePath, Namespace ns)

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[learn-build-service-prod]

Learn Build status updates of commit 9204e7f:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Reflection.Emit/AssemblyBuilder.xml	✅Succeeded	View
xml/System.Reflection/Assembly.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 5f8b34d:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Reflection.Emit/AssemblyBuilder.xml	✅Succeeded	View
xml/System.Reflection/Assembly.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

[jkotas]

AppDomain.IsFullyTrusted is a sibling of this api. Should it get the same treatment?

[learn-build-service-prod]

Learn Build status updates of commit ace30ef:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Reflection/Assembly.xml	✅Succeeded	View
xml/System/AppDomain.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