[BUG] findingTokenStatus accidentally released on both FE and BE

Problem

It looks like !190440 (merged) introduced this field to both backend and frontend which triggered multiversion compatibility error. For GitLab.com the problem should be resolved in the next 24 hours (as soon as new frontend node won’t hit old backend node anymore) but for self-managed this will be a problem for upcoming milestone (unless we fix it now).

Implementation Plan

• Remove ee/app/assets/javascripts/security_dashboard/graphql/fragments/vulnerability.fragment.graphql
• remove findingTokenStatus from ee/spec/frontend/security_dashboard/components/mock_data.js
• Verify if documentation needs to change for doc/api/graphql/reference/_index.md