Fix RandomVariable static type shape bug

[ricardoV94]

This bug showed up in pymc-devs/pymc#6947

import pytensor.tensor as pt

p = pt.ones(3) / 3
x = pt.random.categorical(p=pt.stack([p, 1-p], axis=-1))
assert x.type.shape == (3,)  # AssertionError

Which would later lead to a rewrite error during compilation.

It was caused by the presence of np.int in the static shape of Join, (and corresponding np.bool in the broadcastable), which would then be overlooked by an explicit check broadcastable is False in the RandomVariable.infer_shape.

[codecov-commenter]

Codecov Report

Merging #475 (f236f96) into main (36df379) will increase coverage by 0.00%.
Report is 1 commits behind head on main.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #475   +/-   ##
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  Coverage   80.66%   80.66%           
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  Files         160      160           
  Lines       46025    46029    +4     
  Branches    11266    11268    +2     
=======================================
+ Hits        37124    37128    +4     
  Misses       6668     6668           
  Partials     2233     2233           

Files	Coverage Δ
pytensor/tensor/random/op.py	96.25% <ø> (ø)
pytensor/tensor/type.py	94.52% <100.00%> (+0.04%)	⬆️