Fix deprecation warnings with numpy 2.5

[antonio-rojas]

Fixes

File "/usr/share/doc/sage/html/en/thematic_tutorials/_sources/numerical_sage/numpy.rst.txt", line 173, in numpy.rst
Failed example:
    n.shape=(5,5)
Expected nothing
Got:
    doctest:warning
      File "<doctest numpy.rst[32]>", line 1, in <module>
        n.shape=(Integer(5),Integer(5))
      File "/usr/lib/python3.14/_py_warnings.py", line 230, in _showwarnmsg
        sw(msg.message, msg.category, msg.filename, msg.lineno,
    :
    DeprecationWarning: Setting the shape on a NumPy array has been deprecated in NumPy 2.5.
    As an alternative, you can create a new view using np.reshape (with copy=False if needed).

[github-actions]

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