Finalize BBM UpdateOwaspTop10DefaultOfVulnerabilityReads and remove FF

We have solved the performance concern for Non OWASP category by having -1 represent them in the DB table in #473748 (closed).

Creating this issue to capture the following work from the above issue which can be done only in %17.6 after the required stop:

  1. Finalize BBM UpdateOwaspTop10DefaultOfVulnerabilityReads
  2. Remove FF [Feature flag] Enable owasp_top_10_null_filtering (#463783 - closed)
  3. Celebrate the grouping feature with a release post.
Edited by Bala Kumar