Document symbols don't appear for classes and enums with attributes

[sean-mcmanus]

Environment

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Bug Summary and Steps to Reproduce

Use the repro code

Expected behavior

Document symbols should appear. Go to def and find all refs my fail too.

Code sample and Logs

enum [[nodiscard]] ee1 { ee };
enum class [[nodiscard]] ec1 { ec };
struct [[nodiscard]] es1{};
class [[nodiscard]] c1 {};

Screenshots

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Additional context

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