chore: enable var-declaration from revive

[mmorel-35]

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Please add a summary of your change

enable and fixes var-declaration rule from revive

Does your change fix a particular issue?

Fixes #(issue)

Please indicate you've done the following:

• 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 59.39%. Comparing base (a9031eb) to head (cfe0524).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8636   +/-   ##
=======================================
  Coverage   59.39%   59.39%           
=======================================
  Files         370      370           
  Lines       39952    39952           
=======================================
  Hits        23730    23730           
  Misses      14731    14731           
  Partials     1491     1491           

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