Add RequiresDynamicCodeAttribute to runtime

[tlakollo]

Implements the API in #61239

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Issue Details

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Implements the API in #61239

Author:	tlakollo
Assignees:	tlakollo
Labels:	new-api-needs-documentation, linkable-framework
Milestone:	-

[MichalStrehovsky]

Thank you!

[MichalStrehovsky]

This is a copypaste from RequiresUnreferencedCodeAttribute where this is likely needed because the attribute is included from multiple projects. It's not necessary here at the moment.

[tlakollo]

I was doing some tests with the CodeFixer in the analyzer space and it generates "error CS8632: The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.". The warning disappears if I add the nullable enable statement in the attribute

[tlakollo]

Ah I see now the Url is marked as nullable

[stephentoub]

Thanks