feat: add layer argument for sc.tl.score_genes_cell_cycle

[shinthor]

Simple addition of the layer argument which is already included in sc.tl.score_genes so that you can use your own layer instead of being restricted to what is stored in adata.X

• [ ] Closes #
• [x] Tests included or not required because:

• [ ] Release notes not necessary because:

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 76.52%. Comparing base (208115d) to head (4ed4477).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3138   +/-   ##
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  Coverage   76.52%   76.52%           
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  Files         109      109           
  Lines       12483    12483           
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  Hits         9553     9553           
  Misses       2930     2930           

Files	Coverage Δ
src/scanpy/tools/_score_genes.py	85.10% <0.00%> (ø)

[flying-sheep]

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