Add public list API doc (#1976)

docs/docs/content/apis/lists.md

@@ -3,6 +3,7 @@
 | Method | Endpoint                                        | Description               |
 |:-------|:------------------------------------------------|:--------------------------|
 | GET    | [/api/lists](#get-apilists)                     | Retrieve all lists.       |
+| GET    | [/api/public/lists](#get-public-apilists)       | Retrieve public lists.|
 | GET    | [/api/lists/{list_id}](#get-apilistslist_id)    | Retrieve a specific list. |
 | POST   | [/api/lists](#post-apilists)                    | Create a new list.        |
 | PUT    | [/api/lists/{list_id}](#put-apilistslist_id)    | Update a list.            |
@@ -72,6 +73,28 @@ curl -u "username:password" -X GET 'http://localhost:9000/api/lists?page=1&per_p
 
 ______________________________________________________________________
 
+#### GET /api/public/lists
+
+Retrieve public lists with name and uuid to submit a subscription. This is an unauthenticated call to enable scripting to subscription form.
+
+##### Example Request
+
+```shell
+curl -X GET 'http://localhost:9000/api/public/lists'
+```
+
+##### Example Response
+
+```json
+[
+  {
+    "uuid": "55e243af-80c6-4169-8d7f-bc571e0269e9",
+    "name": "Opt-in list"
+  }
+]
+```
+______________________________________________________________________
+
 #### GET /api/lists/{list_id}
 
 Retrieve a specific list.