Fix: Use testsuite alloc

[sandro-elsweijer]

Closes #1718

Describe your changes here:
I missed T8_ALLOCs in a new test during a merge.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 74.08%. Comparing base (8c0682c) to head (6201192).
Report is 21 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1717   +/-   ##
=======================================
  Coverage   74.08%   74.08%           
=======================================
  Files          99       99           
  Lines       18619    18619           
=======================================
  Hits        13793    13793           
  Misses       4826     4826           

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