code: public String getProject(String configString) {
      if (configString == null
          || configString.trim().isEmpty()
          || configString.equals(APPENGINE_CONFIG)) {
        throw new GradleException(PROJECT_ERROR);
      }
      if (configString.equals(GCLOUD_CONFIG)) {
        try {
          String gcloudProject = cloudSdkOperations.getGcloud().getConfig().getProject();
          if (gcloudProject == null || gcloudProject.trim().isEmpty()) {
            throw new GradleException("Project was not found in gcloud config");
          }
          return gcloudProject;
        } catch (IOException
            | CloudSdkOutOfDateException
            | ProcessHandlerException
            | CloudSdkNotFoundException
            | CloudSdkVersionFileException ex) {
          throw new GradleException("Failed to read project from gcloud config", ex);
        }
      }
      return configString;
    }
docs: Process user configuration of "projectId". If set to GCLOUD_CONFIG then read from gcloud's
  global state. If set but not a keyword then just return the set value.