Complete silver and gold for Knative OpenSSF Best Practice

We currently have a passing level criteria for [Knative OpenSSF Best Practice](https://bestpractices.coreinfrastructure.org/en/projects/5913) but we have not completed the questionnaire for silver and gold this issue is to track that work

Start with the linked Knative OpenSSF Best Practice questionnaire and review the project's currently passing-level criteria. Determine what evidence is needed for the silver and gold sections, then complete those questionnaire sections and verify that the project record reflects the updated responses.

Written by the indexing model from the issue text.