code: public Runner enableRunner(Object projectIdOrPath, Integer runnerId) throws GitLabApiException {
          GitLabApiForm formData = new GitLabApiForm().withParam("runner_id", runnerId, true);
          Response response = post(Response.Status.CREATED, formData.asMap(),
                  "projects", getProjectIdOrPath(projectIdOrPath), "runners");
          return (response.readEntity(Runner.class));
      }
docs: Enable an available specific runner in the project.
  
  <pre><code>GitLab Endpoint: POST /projects/:id/runners</code></pre>
  
  @param projectIdOrPath the project in the form of an Integer(ID), String(path), or Project instance
  @param runnerId  The ID of a runner
  @return Runner instance of the Runner enabled
  @throws GitLabApiException if any exception occurs