fix: update xanadu tests to use with pytest.raise

[AbeCoull]

Issue #, if available:

Description of changes:
fix: update xanadu tests to use with pytest.raise

Testing done:

Merge Checklist

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (6de44e9) to head (b956d3b).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #178   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           99        99           
  Lines         1478      1478           
  Branches        27        27           
=========================================
  Hits          1478      1478           

Flag	Coverage Δ
	100.00% <ø> (?)

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