Backport PR #3048: (feat): raising errors where backed is not supported

[meeseeksmachine]

Backport PR #3048: (feat): raising errors where backed is not supported

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 75.87%. Comparing base (b3b9d05) to head (0948c80).
Report is 39 commits behind head on 1.10.x.

Additional details and impacted files

@@            Coverage Diff             @@
##           1.10.x    #3072      +/-   ##
==========================================
+ Coverage   75.80%   75.87%   +0.07%     
==========================================
  Files         110      110              
  Lines       12500    12532      +32     
==========================================
+ Hits         9475     9509      +34     
+ Misses       3025     3023       -2     

Files with missing lines	Coverage Δ
scanpy/_utils/__init__.py	75.10% <100.00%> (+0.53%)	⬆️
scanpy/preprocessing/_pca.py	92.93% <100.00%> (+0.15%)	⬆️
scanpy/preprocessing/_scale.py	91.96% <100.00%> (+0.07%)	⬆️
scanpy/preprocessing/_simple.py	87.95% <100.00%> (+0.38%)	⬆️
scanpy/tools/_dendrogram.py	86.95% <100.00%> (+0.28%)	⬆️
scanpy/tools/_ingest.py	77.33% <100.00%> (+0.10%)	⬆️
scanpy/tools/_rank_genes_groups.py	94.33% <100.00%> (+0.01%)	⬆️
scanpy/tools/_score_genes.py	85.54% <100.00%> (+0.35%)	⬆️
scanpy/tools/_tsne.py	93.18% <100.00%> (+0.15%)	⬆️

... and 2 files with indirect coverage changes