`_xxsubinterpreters`: the name of shared exception type is `str(exc_type)`, not `exc_type.__name__`

[chgnrdv]

Example:

>> import _xxsubinterpreters
>> i = _xxsubinterpreters.create()
>> _xxsubinterpreters.run_string(i, "(")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
_xxsubinterpreters.RunFailedError: <class 'SyntaxError'>: '(' was never closed (<string>, line 1)

It happens because in _sharedexception_bind %S format specifier is used and exception type is passed to PyUnicode_FromFormat, i. e. PyObject_Str is called on exception type in order to get its name:

cpython/Modules/_xxsubinterpretersmodule.c

Line 272 in 34e93d3

PyObject *nameobj = PyUnicode_FromFormat("%S", Py_TYPE(exc));

I'll send a PR soon.

Linked PRs

• gh-105873: Make _xxsubinterpreters use exception type name in shared exception #105874