fix(examples): Instantiate Session before reading account/region (#6038)

optimize-example.ipynb called Session.account_id() and Session.boto_region_name on the Session class, raising 'TypeError: account_id() missing 1 required positional argument: self'. Create a Session instance first and read the values from it.

Co-authored-by: hrehard <hrehard@amazon.com>

Author: Hannah14295

v3-examples/inference-examples/optimize-example.ipynb

@@ -54,8 +54,9 @@
     "MODEL_ID = \"meta-textgeneration-llama-3-8b-instruct\"\n",
     "MODEL_NAME_PREFIX = \"jumpstart-optimize-example\"\n",
     "ENDPOINT_NAME_PREFIX = \"jumpstart-optimize-example-endpoint\"\n",
-    "AWS_ACCOUNT_ID = Session.account_id()\n",
-    "AWS_REGION = Session.boto_region_name\n",
+    "session = Session()\n",
+    "AWS_ACCOUNT_ID = session.account_id()\n",
+    "AWS_REGION = session.boto_region_name\n",
     "\n",
     "# Generate unique identifiers\n",
     "unique_id = str(uuid.uuid4())[:8]\n",