Replace flake8 and isort

[flpm]

Issue number of the reported bug or feature request: #346

Describe your changes

• Removed pre-commit check for flake8
• Removed setup.cfg (flake8 config)
• Added a pre-commit check for ruff that covers flake8 checks and isort for Python files (.py and .pyi)
• Prevented isort pre-commit check from running on Python files

Testing performed

• Verified that ruff is fixing import order in .py and .pyi files (tested by introducing wrong order)
• Verified that ruff is fixing flake8 rules (tested by introducing unused import)

Additional context
Some isort options are not supported by ruff.

Option multi_line_output = 3 (break multiple imports in multiple lines using parenthesis) is not supported by ruff. The default behavior is the same as multi_line_output = 7 (all imports in one line without breaks), which used along force-single-line = true causes the multiple import to be split into individual imports. For example:

from collections import Counter, defaultdict, deque

is reformatted to:

from collections import Counter
from collections import defaultdict
from collections import deque

Options include_trailing_comma = true and force_grid_wrap = 0 are related to multi_line_output = 3 and are not applicable in ruff.

Option use_parentheses = true is also not supported, but because imports are in individual lines and line-length = 95, removing it would be very unlikely to cause problems.

Some references:
Use Parentheses in isort documnentation
Multi Line Output Modes in isort documentation
Flake 8 rules
Ruff rules

[godlygeek]

LGTM