Validate ILLink support for ref structs within generics

[sbomer]

We need to ensure that Cecil and ILLink correctly preserve the metadata for ref structs used as generic arguments. As mentioned in #65112 (comment), we can use IL tests for this in illink. Part of #65112

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Issue Details

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We need to ensure that Cecil and ILLink correctly preserve the metadata for ref structs used as generic arguments. As mentioned in #65112 (comment), we can use IL tests for this in illink. Part of #65112

Author:	sbomer
Assignees:	-
Labels:	untriaged, area-Tools-ILLink, needs-area-label
Milestone:	-

[vitek-karas]

See #65112 (comment) for Cecil.