Annotating Native CoreLib library to be AOT friendly

[LakshanF]

Propagated RequiresDynamicCode attribute that are tagged on API's that are dangerous for Native AOT within CoreLib to make the library to be AOT friendly.

Required adding the annotation to the public surface area which in turn required the reference APIs to be annotated (and the CoreCLR and Mono library implementation to be annotated)

[ghost]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, to please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[ghost]

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Issue Details

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Propagated RequiresDynamicCode attribute that are tagged on API's that are dangerous for Native AOT within CoreLib to make the library to be AOT friendly.

Required adding the annotation to the public surface area which in turn required the reference APIs to be annotated (and the CoreCLR and Mono library implementation to be annotated)

Author:	LakshanF
Assignees:	LakshanF
Labels:	area-System.Reflection, new-api-needs-documentation
Milestone:	-

[MichalStrehovsky]

Thank you!