Test failure with Python 3.12

[fabaff]

One test (objects.get_vars) fails with Python 3.12 while it passes with older Python releases.

============================= test session starts ==============================
platform linux -- Python 3.12.1, pytest-7.4.4, pluggy-1.4.0 -- /nix/store/y4dxr00qg40pwgxx9nxj61091zk8bsvl-python3-3.12.1/bin/python3.12
cachedir: .pytest_cache
rootdir: /build/uqbar-0.7.1
configfile: pyproject.toml
testpaths: tests, uqbar
collected 142 items / 6 deselected / 136 selected                              

tests/test_apis_APIBuilder.py::test_collection_01 PASSED                 [  0%]
[...]
uqbar/objects.py::uqbar.objects.get_repr PASSED                          [ 79%]
uqbar/objects.py::uqbar.objects.get_vars FAILED                          [ 80%]
uqbar/objects.py::uqbar.objects.new PASSED                               [ 80%]
[...]
uqbar/graphs/records.py::uqbar.graphs.records.RecordGroup PASSED         [100%]

=================================== FAILURES ===================================
_______________________ [doctest] uqbar.objects.get_vars _______________________
191         >>> my_object = MyObject('a', 'b', 'c', 'd', foo='x', quux=['y', 'z'])
192 
193     ::
194 
195         >>> import uqbar
196         >>> args, var_args, kwargs = uqbar.objects.get_vars(my_object)
197 
198     ::
199 
200         >>> args
Expected:
    OrderedDict([('arg1', 'a'), ('arg2', 'b')])
Got:
    OrderedDict({'arg1': 'a', 'arg2': 'b'})

/build/uqbar-0.7.1/uqbar/objects.py:200: DocTestFailure

[josiah-wolf-oberholtzer]

Thanks. Cutting a new release shortly.