fix: Remove trailing whitespace from blank line in json.ipynb

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: dimitri-yatsenko

docs/src/archive/tutorials/json.ipynb

@@ -85,22 +85,11 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 3,
+   "execution_count": null,
    "id": "4aaf96db-85d9-4e94-a4c3-3558f4cc6671",
    "metadata": {},
    "outputs": [],
-   "source": [
-    "@schema\n",
-    "class Team(dj.Lookup):\n",
-    "    definition = \"\"\"\n",
-    "    # A team within a company\n",
-    "    name: varchar(40)  # team name\n",
-    "    ---\n",
-    "    car=null: json  # A car belonging to a team (null to allow registering first but specifying car later)\n",
-    "    \n",
-    "    unique index(car.length:decimal(4, 1))  # Add an index if this key is frequently accessed\n",
-    "    \"\"\""
-   ]
+   "source": "@schema\nclass Team(dj.Lookup):\n    definition = \"\"\"\n    # A team within a company\n    name: varchar(40)  # team name\n    ---\n    car=null: json  # A car belonging to a team (null to allow registering first but specifying car later)\n\n    unique index(car.length:decimal(4, 1))  # Add an index if this key is frequently accessed\n    \"\"\""
   },
   {
    "cell_type": "markdown",
@@ -1077,4 +1066,4 @@
  },
  "nbformat": 4,
  "nbformat_minor": 5
-}
+}