API Fuzz testing configuration
## Feature flags
<!--
#### `feature_flag_name`
* **Status:**
* **staging:**
* **production:**
* **Purpose:**
* **Rollout issue:**
* **YAML:**
-->
### Active
None
### Past
#### `api_fuzzing_configuration_ui`
* **Status:** [Removed](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/57583).
* **Purpose:** Controls the availability of the API fuzz testing configuration page.
* **Rollout issue:** https://gitlab.com/gitlab-org/gitlab/-/issues/299465
* **YAML:** [`config/feature_flags/development/api_fuzzing_configuration_ui.yml`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/config/feature_flags/development/api_fuzzing_configuration_ui.yml)
epic