Add ability to pass in fields to new vulnerability list component

What does this MR do and why?

Previously, the vulnerability list had a fields computed property that defined all the possible fields across all the report levels, then used a skip property to decide which fields should be shown depending on the report level. This MR changes it so that the parent component that uses the vulnerability list decides which fields to show by passing in the fields prop.

Note that this MR modifies a clone of the vulnerability list that is currently not in use. This is setup work for it to be used in a later MR.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #338790 (closed)