Add CI_JOB_STATUS predefined variable to documentation

doc/ci/variables/predefined_variables.md

@@ -69,6 +69,7 @@ Kubernetes-specific environment variables are detailed in the
 | `CI_JOB_MANUAL`                               | 8.12   | all    | The flag to indicate that job was manually started                                                                                                                                                                                                                                                                                                         |
 | `CI_JOB_NAME`                                 | 9.0    | 0.5    | The name of the job as defined in `.gitlab-ci.yml`                                                                                                                                                                                                                                                                                                         |
 | `CI_JOB_STAGE`                                | 9.0    | 0.5    | The name of the stage as defined in `.gitlab-ci.yml`                                                                                                                                                                                                                                                                                                       |
+| `CI_JOB_STATUS`                               | all    | 13.5   | The state of the job as each runner stage is executed. Use with [`after_script`](../yaml/README.md#before_script-and-after_script) where `CI_JOB_STATUS` can be either: `success`, `failed` or `canceled`.                                                                                                                                                                              |
 | `CI_JOB_TOKEN`                                | 9.0    | 1.2    | Token used for authenticating with the [GitLab Container Registry](../../user/packages/container_registry/index.md), downloading [dependent repositories](../../user/project/new_ci_build_permissions_model.md#dependent-repositories), and accessing [GitLab-managed Terraform state](../../user/infrastructure/index.md#gitlab-managed-terraform-state).         |
 | `CI_JOB_JWT`                                  | 12.10  | all    | RS256 JSON web token that can be used for authenticating with third party systems that support JWT authentication, for example [HashiCorp's Vault](../examples/authenticating-with-hashicorp-vault). |
 | `CI_JOB_URL`                                  | 11.1   | 0.5    | Job details URL                                                                                                                                                                                                                                                                                                                                            |