Replace hash with unsafe_hash

[kasium]

Background: https://www.attrs.org/en/stable/changelog.html#deprecations

Closes #485

[cooperlees]

Thanks.

Is 3.13 introducing a new type for single char strings or something?

  ======================================================================
  FAIL: test_b907_format_specifier_permutations (__main__.BugbearTestCase.test_b907_format_specifier_permutations)
  ----------------------------------------------------------------------
  Traceback (most recent call last):
    File "/home/runner/work/flake8-bugbear/flake8-bugbear/tests/test_bugbear.py", line 765, in test_b907_format_specifier_permutations
      old = format_string.format("hello")
  ValueError: Unknown format code 'b' for object of type 'str'

  During handling of the above exception, another exception occurred:

  Traceback (most recent call last):
    File "/home/runner/work/flake8-bugbear/flake8-bugbear/tests/test_bugbear.py", line 768, in test_b907_format_specifier_permutations
      visitor.errors == []
  AssertionError: b907 raised for 'b' not valid for string

  ----------------------------------------------------------------------

[kasium]

Not that I'm aware off. Let me check it tomorrow

[kasium]

I cannot reproduce it locally. I think the whole error is misleading. As far as I can tell from the code, the error is, that visitor.errors == [] which sounds like test pollution.

[JelleZijlstra]

Might be the same AST thing I mentioned in #487

[kasium]

I think so, too. I used the latest greates 3.13-dev and everything worked