curl --request POST '<https://xxxxxxxxxxx/api/plan>' \
--header 'X-Atlantis-Token: xxxxxxxxxx' \
--header 'Content-Type: application/json' \
--data-raw '{
    "Repository": "path/to/repo",
    "Ref": "featurebranch",
    "Type": "Gitlab",
    "Paths": [{
      "Directory": "path/to/terraformdir",
      "Workspace": "workspacename"
    }]
}' | jq .
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   922  100   641  100   281    188     82  0:00:03  0:00:03 --:--:--   270
{
  "Error": null,
  "Failure": "",
  "ProjectResults": [
    {
      "Command": 1,
      "SubCommand": "",
      "RepoRelDir": "path/to/terraformdir",
      "Workspace": "workspacename",
      "Error": null,
      "Failure": "This project is currently locked by an unapplied plan from pull !2. To continue, delete the lock from !2 or apply that plan and merge the pull request.\n\nOnce the lock is released, comment `atlantis plan` here to re-plan.",
      "PlanSuccess": null,
      "PolicyCheckResults": null,
      "ApplySuccess": "",
      "VersionSuccess": "",
      "ImportSuccess": null,
      "StateRmSuccess": null,
      "ProjectName": "projectname"
    }
  ],
  "PlansDeleted": false
}