Update pyflakes to 3.0.0

[pyup-bot]

This PR updates pyflakes from 2.3.1 to 3.0.0.

Changelog

3.0.0

- Detect undefined name in variable defined by an annotated assignment
- Add a new error for names which are annotated but unused
- Remove handling of python 2.x `` type:`` comments.  Use annotations instead

2.5.0

- Drop support for EOL python 2.7 / 3.4 / 3.5
- Ignore ``__all__`` when not directly assigned
- Handle ``TypeAlias`` annotations as aliases (PEP 613)
- Assignment expressions (``:=``) target outer scope in comprehensions
- Add support for new python 3.11 syntax
- Unify output so it is always ``filename:lineno:col:  message``
- Properly report ``SyntaxError`` from stdin in python < 3.9
- Fix offsets of ``SyntaxError``s in pypy

2.4.0

- Remove unused tracing code (``traceTree``)
- Add support for ``match`` statement
- Detect ``typing`` module attributes when imported with ``import ... as ...``

Links

• PyPI: https://pypi.org/project/pyflakes
• Changelog: https://pyup.io/changelogs/pyflakes/
• Repo: https://github.com/PyCQA/pyflakes

[pyup-bot]

Closing this in favor of #523