Added note about differences in Sphinx version and docs

Author: HChughtai

ch04packaging/04documentation.ipynb

@@ -141,7 +141,8 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "Install Sphinx using the [appropiate instructions](https://www.sphinx-doc.org/en/master/usage/installation.html) for your system following the documentation online."
+    "Install Sphinx using the [appropiate instructions](https://www.sphinx-doc.org/en/master/usage/installation.html) for your system following the documentation online.\n",
+    "(Note that your output and the linked documentation may differ slightly depending on when you installed Sphinx and what version you're using.)"
    ]
   },
   {
@@ -151,7 +152,7 @@
     "\n",
     "Invoke the [sphinx-quickstart](https://www.sphinx-doc.org/en/master/usage/quickstart.html) command to build Sphinx's\n",
     "configuration file automatically based on questions\n",
-    "at the command line:\n"
+    "at the command line:"
    ]
   },
   {