refactor: remove unnecessary depinject usage

[julienrbrt]

Description

I was doing that when refactoring some tests due to my incoming integration tests PR refactoring.
This removes the usage of depinject.Inject where a simple helper function can do the same.
The goal is to eventually be able to only keep the usage of module's AppConfig when creating a minimal app with simtestutil.

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• confirmed the correct type prefix in the PR title
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[julienrbrt]

VSCode said that С and C are different characters.
Personally I cannot see it :D