[MAINT] apply black and pre-commit hooks to files not in PRs

[Remi-Gau]

• Closes none

[github-actions]

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[codecov]

Codecov Report

Merging #3906 (5027e8e) into main (fd75801) will not change coverage.
The diff coverage is 96.00%.

@@           Coverage Diff           @@
##             main    #3906   +/-   ##
=======================================
  Coverage   91.74%   91.74%           
=======================================
  Files         134      134           
  Lines       15738    15738           
  Branches     3275     3275           
=======================================
  Hits        14439    14439           
  Misses        757      757           
  Partials      542      542           

Flag	Coverage Δ
macos-latest_3.10	91.65% <96.00%> (ø)
macos-latest_3.11	91.65% <96.00%> (ø)
macos-latest_3.8	91.62% <96.00%> (ø)
macos-latest_3.9	91.62% <96.00%> (ø)
ubuntu-latest_3.10	91.65% <96.00%> (ø)
ubuntu-latest_3.11	91.65% <96.00%> (ø)
ubuntu-latest_3.8	91.62% <96.00%> (ø)
ubuntu-latest_3.9	91.62% <96.00%> (ø)
windows-latest_3.10	91.59% <96.00%> (ø)
windows-latest_3.11	91.59% <96.00%> (ø)
windows-latest_3.8	91.56% <96.00%> (ø)
windows-latest_3.9	91.56% <96.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
nilearn/plotting/displays/_axes.py	96.91% <94.54%> (ø)
nilearn/plotting/glass_brain.py	82.43% <100.00%> (ø)

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[ymzayek]

Thx @Remi-Gau !