Ensure gc collects memory for CriticalFinalizer test

[HJLeee]

Test assumes GC.Collect() successfully collects allocated Normal and Critical objects.

Finalized 0 Normal and 0 Critical objects.
The first Critical object was finalized after 0 Normal objects.

https://helixre107v0xdeko0k025g8.blob.core.windows.net/dotnet-runtime-refs-pull-76007-merge-ac12cc893b1f4aa0bc/baseservices.finalization/1/console.34afcb43.log?helixlogtype=result

[ghost]

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

[AntonLapounov]

Thank you. This does not answer the question why the array is not collected on the first GC.Collect() call. I think assigning arr = null may be a better fix; testing that now.

[HJLeee]

Please close this if arr = null is successful. :)

[ghost]

Tagging subscribers to this area: @dotnet/gc
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Test assumes GC.Collect() successfully collects allocated Normal and Critical objects.

Finalized 0 Normal and 0 Critical objects.
The first Critical object was finalized after 0 Normal objects.

https://helixre107v0xdeko0k025g8.blob.core.windows.net/dotnet-runtime-refs-pull-76007-merge-ac12cc893b1f4aa0bc/baseservices.finalization/1/console.34afcb43.log?helixlogtype=result

Author:	HJLeee
Assignees:	-
Labels:	area-GC-coreclr, community-contribution
Milestone:	-

[AntonLapounov]

Investigating the root issue here: #76041 (comment).