python 3.11 compatiblity

[Sandro]

When executing migrate on python 3.11 the following error is produced due to the deprecation of inspect.getargspec

Traceback (most recent call last):
  File "/nix/store/7a8iky58c7smv24ybgw4x592c9hn7rny-python3.11-sqlalchemy-migrate-0.13.0/bin/.migrate-wrapped", line 9, in <module>
    sys.exit(main())
             ^^^^^^
  File "/nix/store/7a8iky58c7smv24ybgw4x592c9hn7rny-python3.11-sqlalchemy-migrate-0.13.0/lib/python3.11/site-packages/migrate/versioning/shell.py", line 111, in main
    f_args, f_varargs, f_kwargs, f_defaults = inspect.getargspec(command_func)
                                              ^^^^^^^^^^^^^^^^^^
AttributeError: module 'inspect' has no attribute 'getargspec'. Did you mean: 'getargs'?

[lukn (lukn)]

the fix is as simple as replacing line 111 of shell.py by:

f_args, f_varargs, f_kwargs, f_defaults, _, _, _ = inspect.getfullargspec(command_func)