[SYSTEMDS-3172] Sparse CSC Block

[ReneEnjilian]

This PR is just a supplement to a previous task and implements the Sparse CSC Block. MCSC and CSC will most likely only be used for some experiments (@Baunsgaard ) and there will not be a deeper integration for now. Other systems such as PyTorch support both row and column oriented matrix compression formats and now SystemDS does too. I implemented both the row and the column APIs. Further, testing has been added.

[codecov]

Codecov Report

Attention: Patch coverage is 46.58470% with 391 lines in your changes missing coverage. Please review.

Project coverage is 71.02%. Comparing base (9b6a96d) to head (fac5a5f).
Report is 10 commits behind head on main.

Files with missing lines	Patch %	Lines
.../org/apache/sysds/runtime/data/SparseBlockCSC.java	46.36%	371 Missing and 20 partials ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2132      +/-   ##
============================================
- Coverage     71.14%   71.02%   -0.12%     
- Complexity    43048    43173     +125     
============================================
  Files          1446     1447       +1     
  Lines        164246   164978     +732     
  Branches      32018    32170     +152     
============================================
+ Hits         116847   117179     +332     
- Misses        38249    38621     +372     
- Partials       9150     9178      +28     

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[mboehm7]

LGTM - thanks for the additional sparse block @ReneEnjilian. During the merge I fixed remaining warnings, and removed the wildcard imports. Furthermore, some operations are really slow (the sparse component tests now run 300+ seconds) - accordingly, I will do a few runtime improvements in order to reduce this test runtime.