Improve wording around fix_available and false_positive in MR Approval Policies

Proposal

The way these attributes are presented in the policy editor is confusing. The documentation helps clear things up a bit (https://docs.gitlab.com/user/application_security/policies/merge_request_approval_policies/#filter-out-policy-violations-with-the-attributes-fix-available-or-false-positive), but this seems unnecessarily confusing.

A customer shared their experience and feedback (Via this (internal only) ticket), so I'm creating this issue so we can consider a different way of presenting this.