Add rewrite for matmul when only one of the inputs has batched dimensions

[ricardoV94]

Description

This rewrites replaces a batched matmul by a core matmul by raveling the batched dimensions of the batched input, doing a 2D matmul and then unravelling the batched dimensions of the output.

This sidesteps the Blockwise Dot operation and allows specialization into BLAS routines.

The idea was taken from these two discussions:
numpy/numpy#7569
numpy/numpy#8957

Related Issue

• Related to Vectorize follow-up #430

Checklist

• Checked that the pre-commit linting/style checks pass
• Included tests that prove the fix is effective or that the new feature works
• Added necessary documentation (docstrings and/or example notebooks)
• If you are a pro: each commit corresponds to a relevant logical change

Type of change

• New feature / enhancement
• Bug fix
• Documentation
• Maintenance
• Other (please specify):

[codecov-commenter]

Codecov Report

Merging #558 (d28b35f) into main (60a9566) will increase coverage by 0.00%.
The diff coverage is 95.45%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #558   +/-   ##
=======================================
  Coverage   80.91%   80.92%           
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  Files         162      162           
  Lines       46436    46458   +22     
  Branches    11357    11364    +7     
=======================================
+ Hits        37576    37597   +21     
  Misses       6638     6638           
- Partials     2222     2223    +1     

Files	Coverage Δ
pytensor/tensor/rewriting/math.py	87.18% <95.45%> (+0.11%)	⬆️