[jangyoujin0917]

Closes #8523

Updated _is_z_or_cz_pow_gate to recognize the PhasedXZGate when x_exponent is an even integer, making it equivalent to ZPowGate. Added tests for diagonal and non-diagonal PhasedXZGate for drop_diagonal_before_measurement pass.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.58%. Comparing base (7769af9) to head (d7c87d4).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8531      +/-   ##
==========================================
- Coverage   99.59%   99.58%   -0.01%     
==========================================
  Files        1137     1137              
  Lines      105152   105173      +21     
==========================================
+ Hits       104721   104738      +17     
- Misses        431      435       +4     

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