chore: Update ruff, address complaints

[effigies]

The churn machine demands churn.

[effigies]

@DimitriPapadopoulos Care to have a look?

[codecov]

Codecov Report

Attention: Patch coverage is 94.44444% with 1 line in your changes missing coverage. Please review.

Project coverage is 95.34%. Comparing base (f81f5a7) to head (eaa7200).
Report is 31 commits behind head on master.

Files with missing lines	Patch %	Lines
nibabel/cmdline/dicomfs.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1405      +/-   ##
==========================================
- Coverage   95.34%   95.34%   -0.01%     
==========================================
  Files         208      208              
  Lines       29774    29768       -6     
  Branches     3356     3355       -1     
==========================================
- Hits        28387    28381       -6     
  Misses        948      948              
  Partials      439      439              

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[DimitriPapadopoulos]

Finally, perhaps these rules could be enabled:

    "ISC001",
    "ISC002",

Indeed, the documentation has been updated under Conflicting lint rules in astral-sh/ruff#15123 / astral-sh/ruff@b76d05e, in time for 0.9.1:

multi-line-implicit-string-concatenation (ISC002) if used without ISC001 and flake8-implicit-str-concat.allow-multiline = false

The default value of lint.flake8-implicit-str-concat.allow-multiline is true.