Add false-positive for pipeline finding in GraphQL query

What does this MR do?

This MR is related to this issue. In this MR, we are going to expose false-positive information in the GraphQL endpoint for pipeline findings.

With new capabilities of integrating VET to different analyzers, we need to expose false_positive information to the GrapqhQL endpoint for pipeline findings. For now, we are just exposing false_positive as a boolean value that will be used by the frontend to render flags information in the UI.

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How to setup and validate locally (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

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