Fix MLflow logged-models API compat in pipeline tutorial

The curated sklearn-1.5 environment ships MLflow 2.19+ which uses
the logged-models API not supported by AzureML tracking server.
Disable it via MLFLOW_ENABLE_LOGGED_MODELS=false env var.

Author: Chakradhar886

tutorials/get-started-notebooks/pipeline.ipynb

@@ -541,6 +541,7 @@
     "from sklearn.ensemble import GradientBoostingClassifier\n",
     "from sklearn.metrics import classification_report\n",
     "import os\n",
+    "os.environ[\"MLFLOW_ENABLE_LOGGED_MODELS\"] = \"false\"\n",
     "import pandas as pd\n",
     "import mlflow\n",
     "\n",
@@ -946,4 +947,4 @@
  },
  "nbformat": 4,
  "nbformat_minor": 1
-}
+}