Use decomposition instead of Operator.expand

[astralcai]

Operator.expand is deprecated (PennyLaneAI/pennylane#5994). Operator.decomposition should be used instead.

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.99%. Comparing base (27813be) to head (c5e1dc2).
Report is 87 commits behind head on master.

❗ There is a different number of reports uploaded between BASE (27813be) and HEAD (c5e1dc2). Click for more details.

HEAD has 32 uploads less than BASE

Flag	BASE (27813be)	HEAD (c5e1dc2)
	40	8

Additional details and impacted files

@@             Coverage Diff             @@
##           master     #846       +/-   ##
===========================================
- Coverage   98.40%   80.99%   -17.42%     
===========================================
  Files         113       17       -96     
  Lines       18413     1936    -16477     
===========================================
- Hits        18120     1568    -16552     
- Misses        293      368       +75     

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[maliasadi]

LGTM, thanks @astralcai! Feel free to ping me again when you add the PR to ./.github/CHANGELOG.md.

[maliasadi]

🙌

[AmintorDusko]

Thank you very much, @astralcai!