Fix test failures with pyparsing 3.3

[antonio-rojas]

Fixes

File "src/sage/topology/simplicial_set.py", line 1686, in sage.topology.simplicial_set.SimplicialSet_arbitrary.graph
Failed example:
    CP3 = simplicial_sets.ComplexProjectiveSpace(3)
Expected nothing
Got:
    doctest:warning
      File "<doctest sage.topology.simplicial_set.SimplicialSet_arbitrary.graph[6]>", line 1, in <module>
        CP3 = simplicial_sets.ComplexProjectiveSpace(Integer(3))
      File "/usr/lib/python3.14/site-packages/sage/topology/simplicial_set_examples.py", line 622, in ComplexProjectiveSpace
        data = simplicial_data_from_kenzo_output(file)
      File "/usr/lib/python3.14/site-packages/sage/topology/simplicial_set_examples.py", line 678, in simplicial_data_from_kenzo_output
        vertices = OneOrMore(nestedExpr()).parseString(simplex_string).asList()[0]
      File "/usr/lib/python3.14/site-packages/pyparsing/util.py", line 445, in _inner
        warnings.warn(
      File "/usr/lib/python3.14/_py_warnings.py", line 230, in _showwarnmsg
        sw(msg.message, msg.category, msg.filename, msg.lineno,
    :
    DeprecationWarning: 'nestedExpr' deprecated - use 'nested_expr'
    doctest:warning
      File "<doctest sage.topology.simplicial_set.SimplicialSet_arbitrary.graph[6]>", line 1, in <module>
        CP3 = simplicial_sets.ComplexProjectiveSpace(Integer(3))
      File "/usr/lib/python3.14/site-packages/sage/topology/simplicial_set_examples.py", line 622, in ComplexProjectiveSpace
        data = simplicial_data_from_kenzo_output(file)
      File "/usr/lib/python3.14/site-packages/sage/topology/simplicial_set_examples.py", line 678, in simplicial_data_from_kenzo_output
        vertices = OneOrMore(nestedExpr()).parseString(simplex_string).asList()[0]
      File "/usr/lib/python3.14/site-packages/pyparsing/util.py", line 434, in _inner
        warnings.warn(
      File "/usr/lib/python3.14/_py_warnings.py", line 230, in _showwarnmsg
        sw(msg.message, msg.category, msg.filename, msg.lineno,
    :
    DeprecationWarning: 'parseString' deprecated - use 'parse_string'

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