Refactor DependenciesFinder for better separation of concerns

What does this MR do and why?

Refactor DependenciesFinder for better separation of concerns

Move parameter checks inside the filter methods. This makes the code more concise and easier to reason about, since the implementation for each filter does not reside in multiple different methods. This mirrors the approach taken in Security::VulnerabilitiesFinder.

MR acceptance checklist

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