Remove Container Network Security and Container Host Security
### Proposal
The following items are planned to be removed in the GitLab %15.0 release. For additional detail about the deprecation of these items, please reference our [deprecation epic](https://gitlab.com/groups/gitlab-org/-/epics/7476).
- [x] The following helm charts and integrations will be removed and no longer maintained by GitLab
- [x] AppArmor
- [x] Cilium
- [x] Falco
- [x] FluentD
- [x] Pod Security Policies
- [x] The following areas of functionality in the GitLab UI will be removed.
- [x] The entire Statistics tab located on the **Security & Compliance > Threat Monitoring** page.
- [x] The Network Policy type in the **Security & Compliance > Policies** page.
- [x] The `Environment` filter and column on the **Security & Compliance > Policies** page.
- [x] All APIs related to the Container Network and Host Security categories will be removed
- [x] Rails internal API
- [x] Rails GraphQL APIs
- [x] Cilium Alert functionality in the GitLab Agent
- [x] The GitLab Kubernetes Agent code related to CNS will be removed.
- [x] The APIs and all code related to the Alerts tab on the **Security & Compliance > Threat Monitoring** page will be preserved for potential use at a future time. Users will no longer see the **Threat Monitoring** menu option when using GitLab.
- [x] All documentation related to Container Network and Host Security will be removed.
- [x] https://docs.gitlab.com/ee/user/project/clusters/protect/
- [x] https://docs.gitlab.com/ee/user/project/clusters/protect/container_network_security/
- [x] https://docs.gitlab.com/ee/user/project/clusters/protect/container_network_security/quick_start_guide.html
- [x] https://docs.gitlab.com/ee/user/project/clusters/protect/container_host_security/
- [x] https://docs.gitlab.com/ee/user/project/clusters/protect/container_host_security/quick_start_guide.html
- [x] https://docs.gitlab.com/ee/user/application_security/policies/index.html#container-network-policy
- [x] https://docs.gitlab.com/ee/user/application_security/threat_monitoring/
- [x] https://docs.gitlab.com/ee/user/clusters/agent/#kubernetes-network-security-alerts
- [x] https://docs.gitlab.com/ee/user/clusters/agent/repository.html#surface-network-security-alerts-from-cluster-to-gitlab
- [x] Any APIs related to this feature. https://docs.gitlab.com/ee/api/graphql/reference/#networkpolicy is one example; although additional APIs may also need to be removed.
### Other
- Backend DRI: @mparuszewski
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It is important to note that the information presented is for informational purposes only, so please do not rely on the information for purchasing or planning purposes.
Just like with all projects, the items mentioned on the page are subject to change or delay, and the development, release, and timing of any products, features, or functionality remain at the sole discretion of GitLab Inc.*
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epic