[MAINT] Removed all mentions of "License" from headers

[czarinasy]

Closes #3771.

Changes proposed in this pull request:

• Removed the "License" comment from all listed headers

[github-actions]

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[codecov]

Codecov Report

Merging #3838 (cc4db84) into main (01cfa3d) will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #3838      +/-   ##
==========================================
+ Coverage   91.53%   91.57%   +0.03%     
==========================================
  Files         133      133              
  Lines       15623    15616       -7     
  Branches     3250     3248       -2     
==========================================
- Hits        14301    14300       -1     
+ Misses        774      770       -4     
+ Partials      548      546       -2     

Flag	Coverage Δ
macos-latest_3.10	91.49% <ø> (+0.03%)	⬆️
macos-latest_3.11	?
macos-latest_3.8	91.46% <ø> (+0.03%)	⬆️
macos-latest_3.9	91.46% <ø> (+0.03%)	⬆️
ubuntu-latest_3.10	91.49% <ø> (+0.03%)	⬆️
ubuntu-latest_3.11	91.49% <ø> (+0.03%)	⬆️
ubuntu-latest_3.8	91.46% <ø> (+0.03%)	⬆️
ubuntu-latest_3.9	?
windows-latest_3.10	91.43% <ø> (+0.03%)	⬆️
windows-latest_3.11	91.43% <ø> (+0.03%)	⬆️
windows-latest_3.8	91.40% <ø> (+0.03%)	⬆️
windows-latest_3.9	91.40% <ø> (+0.03%)	⬆️

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

Impacted Files	Coverage Δ
nilearn/_utils/cache_mixin.py	80.64% <ø> (ø)
nilearn/_utils/extmath.py	89.47% <ø> (ø)
nilearn/_utils/logger.py	100.00% <ø> (ø)
nilearn/_utils/ndimage.py	88.88% <ø> (ø)
nilearn/_utils/niimg.py	97.11% <ø> (ø)
nilearn/_utils/niimg_conversions.py	90.47% <ø> (ø)
nilearn/_utils/numpy_conversions.py	96.00% <ø> (ø)
nilearn/_utils/testing.py	66.66% <ø> (ø)
nilearn/connectome/group_sparse_cov.py	81.58% <ø> (ø)
nilearn/datasets/neurovault.py	90.49% <ø> (ø)
... and 22 more

... and 1 file with indirect coverage changes

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[ymzayek]

LGTM thanks @czarinasy ! As a first time contributor you also need to add your name to CITATION.cff under authors in alphabetical order by first name.

[czarinasy]

Thanks for the tip @ymzayek! I've made the update now

[Remi-Gau]

LGTM

[Remi-Gau]

Rerunning the CI workflow that cancelled after 6 hours... 99.99999% sure it is unrelated to this but I just want to see how flaky this failure is.

[Remi-Gau]

all green now

merging

thanks @czarinasy