### Background and context Please reference the details provided in the [WAF Deprecation issue](https://gitlab.com/gitlab-org/gitlab/-/issues/271276). * ~backend engineering DRI: @zmartins ### Requirements: 1. GitLab WAF and ModSecurity will be removed from the product 1. GitLab WAF and ModSecurity will be removed from the product documentation 1. Related Modsecurity metrics will be updated to `status: removed`, including (but not limited to) the following files: 1. `config/metrics/counts_all/20210216175442_ingress_modsecurity_packets_processed.yml` 1. `config/metrics/counts_all/20210216175444_ingress_modsecurity_packets_anomalous.yml` 1. `config/metrics/counts_all/20210216175450_ingress_modsecurity_logging.yml` 1. `config/metrics/counts_all/20210216175452_ingress_modsecurity_blocking.yml` 1. `config/metrics/counts_all/20210216175454_ingress_modsecurity_disabled.yml` 1. `config/metrics/counts_all/20210216175456_ingress_modsecurity_not_installed.yml` 1. `config/metrics/settings/20210216175459_ingress_modsecurity_enabled.yml` 1. `ee/config/metrics/counts_all/20210216175441_ingress_modsecurity_statistics_unavailable.yml` 1. Modsecurity will **not** be uninstalled from clusters where it was previously installed upon upgrade from %"13.12" -> %"14.0"; however, GitLab will no longer manage Modsecurity there and a redeploy of the cluster or Ingress node may remove the WAF functionality 1. A verification test will be performed that Ingress can still be installed and that it works properly without ModSecurity 1. [Our packaged ingress configuration](https://gitlab.com/gitlab-org/gitlab/-/blob/a56335b877f1cc3ec85d0dcf5515236835540e78/app/models/clusters/applications/ingress.rb#L93) and [`modsecurity.conf`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/vendor/ingress/modsecurity.conf) will be stored in a public project for historical purposes and for ease of reference if someone should choose to install it manually. This repository and code will be provided as a service to customers, but it will not be actively maintained by GitLab. (for reference, there is [an example](https://gitlab.com/gitlab-org/auto-devops-v12-10) of where this was done in %"13.0")