Fix failing JAX Split test

[ricardoV94]

Test started failing in recent CI. Also tweaked the Split implementation, the checks can only be done with constant inputs.

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📚 Documentation preview 📚: https://pytensor--1646.org.readthedocs.build/en/1646/

[Copilot]

Pull Request Overview

This PR fixes a failing JAX Split test by updating error expectations and refactoring validation logic. The changes ensure that validation checks are only performed when constant inputs are available, preventing runtime errors with traced JAX values.

• Updated test expectations to match the actual errors thrown by the JAX Split implementation
• Refactored Split validation to only perform checks when both axis and splits are constant values

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
tests/link/jax/test_tensor_basic.py	Updated error type expectations from AttributeError to ConcretizationTypeError
pytensor/link/jax/dispatch/tensor_basic.py	Moved validation checks to only run with constant inputs to avoid tracer errors

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.65%. Comparing base (92c3b49) to head (3453c6b).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1646   +/-   ##
=======================================
  Coverage   81.65%   81.65%           
=======================================
  Files         232      232           
  Lines       53087    53088    +1     
  Branches     9403     9404    +1     
=======================================
+ Hits        43348    43349    +1     
  Misses       7286     7286           
  Partials     2453     2453           

Files with missing lines	Coverage Δ
pytensor/link/jax/dispatch/tensor_basic.py	100.00% <100.00%> (ø)

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