Switch test runner to global.json

[Youssef1313]

If dotnet/sdk#50673 gets merged, the insertion of SDK with that change will require the change in this PR.

FYI @LeafShi1 @JeremyKuhne

Microsoft Reviewers: Open in CodeFlow

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.41256%. Comparing base (9634900) to head (f86a01b).

Additional details and impacted files

@@                 Coverage Diff                  @@
##                main      #13849          +/-   ##
====================================================
+ Coverage   77.10424%   97.41256%   +20.30831%     
====================================================
  Files           3273        1209        -2064     
  Lines         644936      357032      -287904     
  Branches       47692        5581       -42111     
====================================================
- Hits          497273      347794      -149479     
+ Misses        143991        8455      -135536     
+ Partials        3672         783        -2889     

Flag	Coverage Δ
Debug	97.41256% <ø> (+20.30831%)	⬆️
integration	?
production	?
test	97.41256% <ø> (ø)
unit	?

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