chore: use Expecter Structs from mockery

[mmorel-35]

Description

Expecter Structs from mockery allows to replace .On("Method") with .EXPECT().Method()

The migration has been done with the help of https://github.com/d0ubletr0uble/expecterlint but it is not a golangci-lint linter and as the argo is in go 1.25, this needs local recompilation to be use so it's not integrated in tooling. By the way testifylint has a task in process by the author of expecterlint to provide it as a new rule.

Covers #24940

Checklist:

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[mmorel-35]

/cc @blakepettersson

[blakepettersson]

LGTM, thanks!

[codecov]

Codecov Report

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Additional details and impacted files

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  Misses            ?    15643           
  Partials          ?     2920           

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