[DOC] update URLs with http:// to https://

[DimitriPapadopoulos]

Update a large part of the URLs in the documentation.

[github-actions]

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[Remi-Gau]

Could you do a cross check on the CITATION.cff file too. That'd be much appreciated. 😉

[codecov]

Codecov Report

Merging #4050 (ab0dae7) into main (b6f4ff0) will increase coverage by 0.09%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #4050      +/-   ##
==========================================
+ Coverage   91.48%   91.57%   +0.09%     
==========================================
  Files         143      143              
  Lines       16076    16076              
  Branches     3340     3340              
==========================================
+ Hits        14707    14722      +15     
+ Misses        823      807      -16     
- Partials      546      547       +1     

Flag	Coverage Δ
macos-latest_3.10	91.47% <100.00%> (ø)
macos-latest_3.11	91.47% <100.00%> (ø)
macos-latest_3.12	91.47% <100.00%> (ø)
macos-latest_3.8	91.43% <100.00%> (ø)
macos-latest_3.9	91.43% <100.00%> (ø)
ubuntu-latest_3.10	91.47% <100.00%> (ø)
ubuntu-latest_3.11	91.47% <100.00%> (ø)
ubuntu-latest_3.12	91.47% <100.00%> (ø)
ubuntu-latest_3.8	91.43% <100.00%> (ø)
ubuntu-latest_3.9	91.43% <100.00%> (ø)
windows-latest_3.10	91.41% <100.00%> (ø)
windows-latest_3.11	91.41% <100.00%> (?)
windows-latest_3.12	91.41% <100.00%> (ø)
windows-latest_3.8	91.37% <100.00%> (ø)
windows-latest_3.9	91.38% <100.00%> (ø)

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

Files	Coverage Δ
nilearn/datasets/atlas.py	93.18% <100.00%> (ø)
nilearn/datasets/func.py	78.66% <ø> (+0.26%)	⬆️
nilearn/datasets/neurovault.py	90.49% <ø> (ø)
nilearn/datasets/struct.py	90.85% <ø> (ø)
nilearn/decoding/proximal_operators.py	70.09% <ø> (ø)
nilearn/decoding/space_net.py	87.32% <ø> (ø)

... and 5 files with indirect coverage changes

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[DimitriPapadopoulos]

I have not modified working http:// URLs that are not redirected to their https:// counterpart, because in that case, I think it's up to the authors to modify their URL.

[bthirion]

LGTM so far. Thx,

[ymzayek]

Thx @DimitriPapadopoulos LGTM!

[ymzayek]

Just need to resolve the conflicts

[Remi-Gau]

Just need to resolve the conflicts

done

[Remi-Gau]

thanks @DimitriPapadopoulos