Add complete state for an answer

Thanks, webadpro for the #2 patch
Facing the following error after the patch

The website encountered an unexpected error. Please try again later.
Error: Call to undefined method Drupal\opigno_module\Entity\OpignoAnswer::isCompleted() in {closure}() (line 2843 of modules/contrib/opigno_learning_path/opigno_learning_path.module).
{closure}()
array_map() (Line: 2849)
{closure}()
array_map() (Line: 2861)
opigno_learning_path_get_module_activities() (Line: 2889)
opigno_learning_path_get_activities() (Line: 2919)
opigno_learning_path_get_activities() (Line: 68)
Drupal\opigno_learning_path\Progress->getProgress() (Line: 127)
Drupal\opigno_learning_path\Progress->getProgressRound() (Line: 548)
Drupal\opigno_learning_path\Progress->getProgressBuildAchievementsPage() (Line: 216)
Drupal\opigno_learning_path\Progress->getProgressBuild() (Line: 164)
Drupal\opigno_learning_path\Progress->getProgressAjaxContainer() (Line: 928)
Drupal\opigno_learning_path\Controller\LearningPathAchievementController->build_training_summary() (Line: 948)
Drupal\opigno_learning_path\Controller\LearningPathAchievementController->build_training() (Line: 1056)
Drupal\opigno_learning_path\Controller\LearningPathAchievementController->Drupal\opigno_learning_path\Controller\{closure}()
array_map() (Line: 1057)
Drupal\opigno_learning_path\Controller\LearningPathAchievementController->buildTrainingProgress()
call_user_func_array() (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 564)
Drupal\Core\Render\Renderer->executeInRenderContext() (Line: 124)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 169)
Symfony\Component\HttpKernel\HttpKernel->handleRaw() (Line: 81)
Symfony\Component\HttpKernel\HttpKernel->handle() (Line: 58)
Drupal\Core\StackMiddleware\Session->handle() (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle() (Line: 106)
Drupal\page_cache\StackMiddleware\PageCache->pass() (Line: 85)
Drupal\page_cache\StackMiddleware\PageCache->handle() (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle() (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle() (Line: 23)
Stack\StackedHttpKernel->handle() (Line: 709)
Drupal\Core\DrupalKernel->handle() (Line: 19)