Adding the `merge_request_author_approval` option to the merge request api...

Adding the `merge_request_author_approval` option to the merge request api configuration section. This option was added in 11.10 with https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/10050.

doc/api/merge_request_approvals.md

@@ -72,12 +72,13 @@ POST /projects/:id/approvals
 
 **Parameters:**
 
-| Attribute                                        | Type    | Required | Description                                                |
-| ------------------------------------------------ | ------- | -------- | ---------------------------------------------------------- |
-| `id`                                             | integer | yes      | The ID of a project                                        |
-| `approvals_before_merge`                         | integer | no       | How many approvals are required before an MR can be merged |
-| `reset_approvals_on_push`                        | boolean | no       | Reset approvals on a new push                              |
-| `disable_overriding_approvers_per_merge_request` | boolean | no       | Allow/Disallow overriding approvers per MR                 |
+| Attribute                                        | Type    | Required | Description                                                   |
+| ------------------------------------------------ | ------- | -------- | ----------------------------------------------------------    |
+| `id`                                             | integer | yes      | The ID of a project                                           |
+| `approvals_before_merge`                         | integer | no       | How many approvals are required before an MR can be merged    |
+| `reset_approvals_on_push`                        | boolean | no       | Reset approvals on a new push                                 |
+| `disable_overriding_approvers_per_merge_request` | boolean | no       | Allow/Disallow overriding approvers per MR                    |
+| `merge_requests_author_approval`                 | boolean | no       | Allow/Disallow authors be able to self approve merge requests |
 
 ```json
 {
@@ -113,7 +114,8 @@ POST /projects/:id/approvals
   ],
   "approvals_before_merge": 2,
   "reset_approvals_on_push": true,
-  "disable_overriding_approvers_per_merge_request": false
+  "disable_overriding_approvers_per_merge_request": false,
+  "merge_requests_author_approval": false
 }
 ```