Revise 'WIP' to 'draft' in API definitions

Don't touch the API endpoints themselves; only change the user-facing
definitions to remove 'WIP' whenever possible. Exceptions: when we're
referring to a specific argument. Those haven't changed yet.

app/graphql/types/merge_request_type.rb

@@ -54,7 +54,7 @@ class MergeRequestType < BaseObject
     field :target_branch, GraphQL::STRING_TYPE, null: false,
           description: 'Target branch of the merge request.'
     field :work_in_progress, GraphQL::BOOLEAN_TYPE, method: :work_in_progress?, null: false,
-          description: 'Indicates if the merge request is a work in progress (WIP).'
+          description: 'Indicates if the merge request is a draft.'
     field :merge_when_pipeline_succeeds, GraphQL::BOOLEAN_TYPE, null: true,
           description: 'Indicates if the merge has been set to be merged when its pipeline succeeds (MWPS).'
     field :diff_head_sha, GraphQL::STRING_TYPE, null: true,

doc/api/graphql/reference/index.md

@@ -2528,7 +2528,7 @@ Autogenerated return type of MarkAsSpamSnippet.
 | `userNotesCount` | Int | User notes count of the merge request. |
 | `userPermissions` | MergeRequestPermissions! | Permissions for the current user on the resource |
 | `webUrl` | String | Web URL of the merge request. |
-| `workInProgress` | Boolean! | Indicates if the merge request is a work in progress (WIP). |
+| `workInProgress` | Boolean! | Indicates if the merge request is a draft. |
 ### MergeRequestCreatePayload

doc/api/merge_requests.md

@@ -101,7 +101,7 @@ Parameters:
 | `target_branch`                 | string         | no       | Return merge requests with the given target branch.                                                                     |
 | `search`                        | string         | no       | Search merge requests against their `title` and `description`.                                                          |
 | `in`                            | string         | no       | Modify the scope of the `search` attribute. `title`, `description`, or a string joining them with comma. Default is `title,description`. |
-| `wip`                           | string         | no       | Filter merge requests against their `wip` status. `yes` to return *only* WIP merge requests, `no` to return *non* WIP merge requests. |
+| `wip`                           | string         | no       | Filter merge requests against their `wip` status. `yes` to return *only* draft merge requests, `no` to return *non-draft* merge requests. |
 | `not`                           | Hash           | no       | Return merge requests that do not match the parameters supplied. Accepts: `labels`, `milestone`, `author_id`, `author_username`, `assignee_id`, `assignee_username`, `reviewer_id`, `reviewer_username`, `my_reaction_emoji`. |
 | `environment`                   | string         | no       | Returns merge requests deployed to the given environment. Expected in ISO 8601 format (`2019-03-15T08:00:00Z`) |
 | `deployed_before`               | datetime       | no       | Return merge requests deployed before the given date/time. Expected in ISO 8601 format (`2019-03-15T08:00:00Z`) |
@@ -287,7 +287,7 @@ Parameters:
 | `source_branch`                 | string         | no       | Return merge requests with the given source branch.                                                                             |
 | `target_branch`                 | string         | no       | Return merge requests with the given target branch.                                                                             |
 | `search`                        | string         | no       | Search merge requests against their `title` and `description`.                                                                  |
-| `wip`                           | string         | no       | Filter merge requests against their `wip` status. `yes` to return *only* WIP merge requests, `no` to return *non* WIP merge requests. |
+| `wip`                           | string         | no       | Filter merge requests against their `wip` status. `yes` to return *only* draft merge requests, `no` to return *non-draft* merge requests. |
 | `not`                           | Hash           | no       | Return merge requests that do not match the parameters supplied. Accepts: `labels`, `milestone`, `author_id`, `author_username`, `assignee_id`, `assignee_username`, `reviewer_id`, `reviewer_username`, `my_reaction_emoji`. |
 ```json