[MT][browser] `customAttributeCount` fails

[ilonatommy]

Failing after enabling all MT library tests (#91536).

 [FAIL] System.Tests.GetCustomAttribute.customAttributeCount
 Assert.Equal() Failure
 Expected: 5
 Actual:   3
   at System.Tests.GetCustomAttribute.customAttributeCount()
   at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
   at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)

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Issue Details

---

Failing after enabling all MT library tests (#91536).

 [FAIL] System.Tests.GetCustomAttribute.customAttributeCount
 Assert.Equal() Failure
 Expected: 5
 Actual:   3
   at System.Tests.GetCustomAttribute.customAttributeCount()
   at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
   at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)

Author:	ilonatommy
Assignees:	-
Labels:	arch-wasm, disabled-test, area-Build-mono, area-VM-threading-mono
Milestone:	-

[pavelsavara]

it would be good to find root cause

[ilonatommy]

It's not blocked, passing, closing.