chore: apply gofumpt in test packages

[mmorel-35]

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chore: apply gofumpt in test packages

Activation in golangci-lint config will happen in a later PR

Does your change fix a particular issue?

Fixes #(issue)

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• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file (make new-changelog) or comment /kind changelog-not-required on this PR.
• Updated the corresponding documentation in site/content/docs/main.

[mmorel-35]

/kind changelog-not-required

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 59.32%. Comparing base (ddc1bcb) to head (656e150).
Report is 9 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8612      +/-   ##
==========================================
+ Coverage   59.16%   59.32%   +0.15%     
==========================================
  Files         370      370              
  Lines       39777    39887     +110     
==========================================
+ Hits        23535    23663     +128     
+ Misses      14745    14728      -17     
+ Partials     1497     1496       -1     

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[kaovilai]

rerunning changelog check.

[reasonerjt]

Thanks for the PR!

I think we've been using gofmt which is official.

Do we wanna use gofumpt which is a fork of gofmt?

I'm tentatively blocking the merge of the PR until the maintainers reach the agreement.