change varible used for completion status to the one used to control …

…the loop

The 2nd step in the Check Customization Job Status section of 03_Model_customization/03_continued_pretraining_titan_text.ipynb never completes as the while variable is not changed in the loop  aws-samples#225

03_Model_customization/03_continued_pretraining_titan_text.ipynb

@@ -449,7 +449,7 @@
  "\n",
  "while training_job_status == \"InProgress\":\n",
  " time.sleep(60)\n",
- " fine_tune_job = bedrock.get_model_customization_job(jobIdentifier=customization_job_name)[\"status\"]\n",
+ " training_job_status = bedrock.get_model_customization_job(jobIdentifier=customization_job_name)[\"status\"]\n",
  " print (training_job_status)"
  ]
  },