Fix typos in notebook readme

Author: jleibs

examples/python/notebook/README.md

@@ -25,7 +25,7 @@ pip install -r requirements.txt
 
 Open the notebook
 ```
-jupyyter notebook cube.ipynb
+jupyter notebook cube.ipynb
 ```
 
 Follow along in the browser that opens.

examples/python/notebook/cube.ipynb

@@ -50,15 +50,16 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "rr.start_web_viewer_server()"
+    "# rr.start_web_viewer_server()"
    ]
   },
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "bf894a1f",
    "metadata": {},
    "source": [
-    "## Helper to the colored cube\n",
+    "## Helper to create the colored cube\n",
     "\n",
     "This is the same as the color cube demo from `rerun -m rerun_demo`, but the code\n",
     "is repeated here for context."