Add documentation for API Fuzzer

doc/user/application_security/index.md

@@ -67,6 +67,7 @@ GitLab uses the following tools to scan and report known vulnerabilities found i
 | [Dependency List](dependency_list/index.md) **(ULTIMATE)**                   | View your project's dependencies and their known vulnerabilities.      |
 | [Dependency Scanning](dependency_scanning/index.md) **(ULTIMATE)**           | Analyze your dependencies for known vulnerabilities.                   |
 | [Dynamic Application Security Testing (DAST)](dast/index.md) **(ULTIMATE)**  | Analyze running web applications for known vulnerabilities.            |
+| [API fuzzing](api_fuzzing/index.md) **(ULTIMATE)**                 | Find unknown bugs and vulnerabilities in web APIs with fuzzing.    |
 | [Secret Detection](secret_detection/index.md) **(ULTIMATE)**                 | Analyze Git history for leaked secrets.                                |
 | [Security Dashboard](security_dashboard/index.md) **(ULTIMATE)**             | View vulnerabilities in all your projects and groups.                  |
 | [Static Application Security Testing (SAST)](sast/index.md)                  | Analyze source code for known vulnerabilities.                         |