[FMT] apply black to maskers - part 1

[Remi-Gau]

Relates to #2528

Changes proposed in this pull request:

• update configs to include nilearn/maskers
• apply black

[github-actions]

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[codecov]

Codecov Report

Merging #3795 (bcfe354) into main (186845c) will not change coverage.
The diff coverage is 96.72%.

@@           Coverage Diff           @@
##             main    #3795   +/-   ##
=======================================
  Coverage   91.52%   91.52%           
=======================================
  Files         133      133           
  Lines       15561    15561           
  Branches     3229     3229           
=======================================
  Hits        14242    14242           
  Misses        772      772           
  Partials      547      547           

Flag	Coverage Δ
macos-latest_3.10	91.44% <96.72%> (?)
macos-latest_3.11	91.44% <96.72%> (?)
macos-latest_3.8	91.41% <96.72%> (?)
macos-latest_3.9	91.41% <96.72%> (?)
ubuntu-latest_3.10	91.44% <96.72%> (?)
ubuntu-latest_3.11	91.44% <96.72%> (ø)
ubuntu-latest_3.8	91.41% <96.72%> (?)
ubuntu-latest_3.9	91.41% <96.72%> (ø)
windows-latest_3.10	91.38% <96.72%> (?)
windows-latest_3.11	91.38% <96.72%> (ø)
windows-latest_3.8	91.35% <96.72%> (ø)
windows-latest_3.9	91.35% <96.72%> (ø)

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

Impacted Files	Coverage Δ
nilearn/maskers/multi_nifti_masker.py	93.18% <94.11%> (ø)
nilearn/maskers/base_masker.py	89.74% <94.44%> (ø)
nilearn/maskers/_masker_validation.py	100.00% <100.00%> (ø)
nilearn/maskers/multi_nifti_labels_masker.py	95.65% <100.00%> (ø)
nilearn/maskers/multi_nifti_maps_masker.py	95.65% <100.00%> (ø)

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