autoupdate pre-commit to v6.0.0 version; update files by black-26.1.0

[AgnieszkaZaba]

New version of black (26.1.0) updated structure of files
release notes
Changing that affected our codebase:

• only one extra empty line after .py file docstring always_one_newline_after_import
• no new line when dealing with Strings (e.g. .replace is after the end of text, not in next line)
• remove_parens_from_assignment_lhs

[codecov]

Codecov Report

❌ Patch coverage is 12.50000% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 86.77%. Comparing base (76506e9) to head (705d2c2).

Files with missing lines	Patch %	Lines
...ckends/impl_numba/methods/fragmentation_methods.py	0.00%	7 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1796   +/-   ##
=======================================
  Coverage   86.77%   86.77%           
=======================================
  Files         414      414           
  Lines       10500    10500           
=======================================
  Hits         9111     9111           
  Misses       1389     1389           

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[AgnieszkaZaba]

addresses #1793

[AgnieszkaZaba]

I don't know if we should test those lines, as it is just syntax change.