`FrozenInstanceError` on 3.13+ for `reify` types with non-frozen bases

[chrisrink10]

Since updating to Python 3.13, reify types created with non-frozen bases (such as any subclass of io/IOBase) emit an attrs FrozenInstanceError typically when the Python VM is shutting down (and __del__ is called, which calls self.close() and which attempts to modify the instance via __setattr__). It is not possible to make reify types mutable (not attrs.frozen), so this is not avoidable at the moment.

(reify* :implements [^:abstract ^{:abstract-members #{:read :write}} io/IOBase]
  (read [this n])
  (write [this v]))

The exception being printed is being caught by the Python sys.unraisablehook since it's happening only at shutdown:

Exception ignored in: ReifiedType_6652(_meta=None)
Traceback (most recent call last):
  File "/Users/christopher/Library/Caches/pypoetry/virtualenvs/basilisp-lKTp5Mxg-py3.13/lib/python3.13/site-packages/attr/_make.py", line 551, in _frozen_setattrs
    raise FrozenInstanceError()
attr.exceptions.FrozenInstanceError:

These are also being reported as warnings via PyTest.

I imagine this isn't actually limited to Python 3.13, but only that it's just now being reported on that version.