remove prep argument

[albi3ro]

In #4756 : PennyLaneAI/pennylane#4756

the prep keyword argument was removed from QuantumScript, completing its deprecation cycle. Now state prep should be placed at the beginning of the ops queue.

[github-actions]

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[codecov]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (ce8597e) 99.00% compared to head (3e11ef5) 97.37%.
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #542      +/-   ##
==========================================
- Coverage   99.00%   97.37%   -1.64%     
==========================================
  Files         167      145      -22     
  Lines       22211    17322    -4889     
==========================================
- Hits        21990    16867    -5123     
- Misses        221      455     +234     

Files	Coverage Δ
pennylane_lightning/core/_version.py	100.00% <100.00%> (ø)
pennylane_lightning/core/lightning_base.py	100.00% <100.00%> (ø)
pennylane_lightning/lightning_gpu/lightning_gpu.py	3.19% <0.00%> (-84.47%)	⬇️

... and 42 files with indirect coverage changes

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[vincentmr]

Looks good to me, thanks @albi3ro for dealing with this so quickly.

[vincentmr]

Codecov is failing expectedly because MPI coverage is lacking.

[AmintorDusko]

Thank you, @albi3ro.