IMetaDataImport::EnumMemberRefs is always empty in .NET 6 preview

[kalikin]

Hello.
In our profiler we have always used IMetaDataImport::EnumMemberRefs without a problem. But in .NET 6.0.100-preview.5.21302.13 the enumerator always appears to be empty, i.e. the pcTokens is always 0.

It is not reproducible on .NET 5.0 and earlier versions. I haven't tried other .NET 6 versions until now.
So far, I've tried the preview only on Linux x64.

I made a small repository which demonstrates the problem.

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[jkotas]

Looks like a regression introduced by #50471

cc @janvorli @tmds