[REF] Fix more f strings

[Remi-Gau]

Relates to #2528

Changes proposed in this pull request:

• fix remaining f strings
• use flake8-use-fstrings to throw errors in case of usage of % or .format()

[github-actions]

👋 @Remi-Gau Thanks for creating a PR!

Until this PR is ready for review, you can include the [WIP] tag in its title, or leave it as a github draft.

Please make sure it is compliant with our contributing guidelines. In particular, be sure it checks the boxes listed below.

• PR has an interpretable title.
• PR links to Github issue with mention Closes #XXXX (see our documentation on PR structure)
• Code is PEP8-compliant (see our documentation on coding style)
• Changelog or what's new entry in doc/changes/latest.rst (see our documentation on PR structure)

For new features:

• There is at least one unit test per new function / class (see our documentation on testing)
• The new feature is demoed in at least one relevant example.

For bug fixes:

• There is at least one test that would fail under the original bug conditions.

We will review it as quick as possible, feel free to ping us with questions if needed.

[codecov]

Codecov Report

Merging #3776 (ad2022f) into main (7d91e88) will increase coverage by 0.00%.
The diff coverage is 80.00%.

@@           Coverage Diff           @@
##             main    #3776   +/-   ##
=======================================
  Coverage   91.52%   91.52%           
=======================================
  Files         133      133           
  Lines       15557    15561    +4     
  Branches     3229     3229           
=======================================
+ Hits        14238    14242    +4     
  Misses        772      772           
  Partials      547      547           

Flag	Coverage Δ
macos-latest_3.10	91.44% <80.00%> (?)
macos-latest_3.11	91.44% <80.00%> (+<0.01%)	⬆️
macos-latest_3.8	91.41% <80.00%> (?)
macos-latest_3.9	91.41% <80.00%> (?)
ubuntu-latest_3.10	91.44% <80.00%> (?)
ubuntu-latest_3.11	91.44% <80.00%> (?)
ubuntu-latest_3.8	91.41% <80.00%> (?)
ubuntu-latest_3.9	91.41% <80.00%> (+<0.01%)	⬆️
windows-latest_3.10	91.38% <80.00%> (+<0.01%)	⬆️
windows-latest_3.11	91.38% <80.00%> (?)
windows-latest_3.8	91.35% <80.00%> (?)
windows-latest_3.9	91.35% <80.00%> (?)

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/datasets/utils.py	75.86% <ø> (ø)
..._testing/_glm_reporter_visual_inspection_suite_.py	88.23% <ø> (ø)
nilearn/_utils/niimg_conversions.py	90.47% <33.33%> (ø)
nilearn/datasets/atlas.py	93.14% <66.66%> (ø)
nilearn/_utils/exceptions.py	100.00% <100.00%> (ø)
nilearn/_utils/logger.py	100.00% <100.00%> (ø)
nilearn/_utils/niimg.py	97.11% <100.00%> (+0.05%)	⬆️
nilearn/_utils/testing.py	66.66% <100.00%> (ø)
nilearn/datasets/func.py	78.52% <100.00%> (ø)
... and 1 more

... and 7 files with indirect coverage changes

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[Remi-Gau]

there are a few string concatenation left here and there in the code base but changing them was actually making it harder to read and they are not flagged as error by flake8-use-fstrings

[ymzayek]

This LGTM! I'm unsure about these azure failures now popping up everywhere. I can try to get an opinion from Azure developers. Let's also see if everything passes on the github tests in #3780

[ymzayek]

Something went wrong with the merge here? See diff

[Remi-Gau]

Something went wrong with the merge here? See diff

oops
indeed

[Remi-Gau]

should look better now

[ymzayek]

LGTM thx!