Merge EE doc/user/application_security/ to CE

Description

Merge EE doc/user/application_security/ to CE

MR workflow

The following are stuff we gathered during our MR tests (e.g., !21089 (closed)) (if you find something that needs to change, comment in &199 (closed)):

  1. Locally copy the EE dir to CE
  2. Create MR
  3. Using our documented EE/CE doc alignment standards:
    1. Convert URLs to relative URLs. If a link fails the check because it does not exist yet in CE (from another to-be-merged section) keep absolute URL. We’ll do a find/replace later.
    2. If a feature was only in EE and had no tier-specific badge, look up the feature and add one. If any question, ask relevant PM.
  4. Create EE equivalent MR
Edited by Marcel Amirault