Add to_project_id parameter to Move Issue via API example

changelogs/unreleased/docs-fix-15669-issue-move-api.yml

+---
+title: Add to_project_id parameter to Move Issue via API example
+merge_request:
+author:
+type: fixed

doc/api/issues.md

@@ -558,7 +558,7 @@ POST /projects/:id/issues/:issue_iid/move
 | `to_project_id` | integer | yes      | The ID of the new project            |
 
 ```bash
-curl --request POST --header "PRIVATE-TOKEN: 9koXpg98eAheJpvBs5tK" https://gitlab.example.com/api/v4/projects/4/issues/85/move
+curl --request POST --header "PRIVATE-TOKEN: 9koXpg98eAheJpvBs5tK" --data '{"to_project_id": 5}' https://gitlab.example.com/api/v4/projects/4/issues/85/move
 ```
 
 Example response: