Remove unnecessary handling of no longer supported RandomState

[ricardoV94]

Small cleanup

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📚 Documentation preview 📚: https://pytensor--1300.org.readthedocs.build/en/1300/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.01%. Comparing base (c822a8e) to head (702889b).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1300      +/-   ##
==========================================
- Coverage   82.03%   82.01%   -0.02%     
==========================================
  Files         188      188              
  Lines       48567    48433     -134     
  Branches     8675     8657      -18     
==========================================
- Hits        39841    39724     -117     
+ Misses       6574     6564      -10     
+ Partials     2152     2145       -7     

Files with missing lines	Coverage Δ
pytensor/link/jax/linker.py	95.00% <100.00%> (ø)
pytensor/link/numba/linker.py	100.00% <100.00%> (+15.00%)	⬆️

... and 12 files with indirect coverage changes

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[Armavica]

There are others at other places of the code, are those still needed?

❯ rg -w RandomState
tests/unittest_tools.py
30:    Useful for seeding RandomState or Generator objects.
31:    >>> rng = np.random.RandomState(fetch_seed())

pytensor/tensor/random/var.py
14:@shared_constructor.register(np.random.RandomState)
19:    r"""`SharedVariable` constructor for NumPy's `Generator` and/or `RandomState`."""
20:    if isinstance(value, np.random.RandomState):
22:            "`np.RandomState` is no longer supported in PyTensor. Use `np.random.Generator` instead."

pytensor/tensor/random/type.py
9:T = TypeVar("T", np.random.RandomState, np.random.Generator)
27:    r"""A Type wrapper for `numpy.random.Generator` and `numpy.random.RandomState`."""

doc/optimizations.rst
242:        Typically when a graph uses random numbers, the RandomState is stored

pytensor/compile/nanguardmode.py
37:    elif isinstance(arr, np.random.mtrand.RandomState | np.random.Generator):

pytensor/compile/monitormode.py
108:            not isinstance(output[0], np.random.RandomState | np.random.Generator)

doc/extending/extending_pytensor_solution_1.py
121:        rng = np.random.RandomState(43)
131:        rng = np.random.RandomState(43)
153:        rng = np.random.RandomState(43)

pytensor/gradient.py
1804:    rng: np.random.Generator | np.random.RandomState | None = None,

doc/library/d3viz/index.rst
61:    rng = np.random.RandomState(0)

doc/library/d3viz/index.ipynb
98:    "rng = np.random.RandomState(0)\n",

tests/tensor/random/test_basic.py
1422:        integers(10, rng=shared(np.random.RandomState()))