QubitStateVector => StatePrep + parametrize tests.

[vincentmr]

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---

Context:
Rename QubitStateVector as StatePrep in Lightning following recent changes in PennyLane PR#4450.

Description of the Change:

Benefits:

Possible Drawbacks:

Related GitHub Issues:

[codecov]

Codecov Report

Merging #486 (e2fb941) into master (e7922ff) will decrease coverage by 0.85%.
Report is 1 commits behind head on master.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #486      +/-   ##
==========================================
- Coverage   97.22%   96.37%   -0.85%     
==========================================
  Files         142       23     -119     
  Lines       16420     1186   -15234     
==========================================
- Hits        15964     1143   -14821     
+ Misses        456       43     -413     

Files Changed	Coverage Δ
pennylane_lightning/core/lightning_base.py	100.00% <ø> (ø)
pennylane_lightning/core/_serialize.py	100.00% <100.00%> (ø)
pennylane_lightning/core/_version.py	100.00% <100.00%> (ø)
...ane_lightning/lightning_kokkos/lightning_kokkos.py	94.07% <100.00%> (+0.09%)	⬆️
...ylane_lightning/lightning_qubit/lightning_qubit.py	92.54% <100.00%> (ø)

... and 131 files with indirect coverage changes

[multiphaseCFD]

Thanks @vincentmr ! I guess we need to change LightningGPU to Lightning in the context above.

[vincentmr]

Thanks @vincentmr ! I guess we need to change LightningGPU to Lightning in the context above.

Indeed. Done, thanks.

[vincentmr]

FYI for Codecov, I have #485 drafted that should fix coverage.

[mlxd]

Let's get this powered through. Thanks @vincentmr

[multiphaseCFD]

Looks good to me! Thanks @vincentmr