Vwp/docs improved document loaders (#4006)

Huge thanks to @leo-gan for improving the document loaders notebooks

---------

Co-authored-by: Leonid Ganeline <leo.gan.57@gmail.com>

docs/modules/indexes/document_loaders/examples/gitbook.ipynb

@@ -6,7 +6,10 @@
    "metadata": {},
    "source": [
     "# GitBook\n",
-    "How to pull page data from any GitBook."
+    "\n",
+    ">[GitBook](https://docs.gitbook.com/) is a modern documentation platform where teams can document everything from products to internal knowledge bases and APIs.\n",
+    "\n",
+    "This notebook shows how to pull page data from any `GitBook`."
    ]
   },
   {
@@ -19,6 +22,14 @@
     "from langchain.document_loaders import GitbookLoader"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "65d5ddce",
+   "metadata": {},
+   "source": [
+    "### Load from single GitBook page"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": 2,
@@ -29,14 +40,6 @@
     "loader = GitbookLoader(\"https://docs.gitbook.com\")"
    ]
   },
-  {
-   "cell_type": "markdown",
-   "id": "65d5ddce",
-   "metadata": {},
-   "source": [
-    "### Load from single GitBook page"
-   ]
-  },
   {
    "cell_type": "code",
    "execution_count": 3,
@@ -178,7 +181,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.9.1"
+   "version": "3.10.6"
   },
   "vscode": {
    "interpreter": {