Add depth_slice() to ImagingExtractors

[weiglszonja]

Add support for slicing over planes for volumetric imaging data. (first example for volumetric imaging: #230)
WIP

[pauladkisson]

This logic should be moved to volumetricimagingextractor.py once #248 is merged.

[codecov]

Codecov Report

Attention: Patch coverage is 94.44444% with 4 lines in your changes are missing coverage. Please review.

Project coverage is 79.71%. Comparing base (c5dedb2) to head (1da7855).
Report is 15 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #231      +/-   ##
==========================================
+ Coverage   79.17%   79.71%   +0.54%     
==========================================
  Files          39       39              
  Lines        3054     3141      +87     
==========================================
+ Hits         2418     2504      +86     
- Misses        636      637       +1     

Flag	Coverage Δ
unittests	79.71% <94.44%> (+0.54%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
...tors/extractors/numpyextractors/numpyextractors.py	65.32% <95.83%> (+4.37%)	⬆️
src/roiextractors/testing.py	98.73% <87.50%> (-0.59%)	⬇️
src/roiextractors/imagingextractor.py	85.29% <95.00%> (+4.04%)	⬆️

[pauladkisson]

@weiglszonja, are you still working on this?

[weiglszonja]

hey @pauladkisson, not actively. do you want to close this for now?

[pauladkisson]

Yeah, since a lot of this needs to be revamped for volumetric imaging extractor, I think we can close this PR and circle back around to it when we have a concrete reason to do so.