docs: add path to state_of_the_union.txt in indexes/getting_started page (#1691)

add the state_of_the_union.txt file so that its easier to follow through
with the example.

---------

Co-authored-by: Jithin James <jjmachan@pop-os.localdomain>

docs/modules/indexes/getting_started.ipynb

@@ -37,7 +37,7 @@
    "id": "07c1e3b9",
    "metadata": {},
    "source": [
-    "Next in the generic setup, let's specify the document loader we want to use."
+    "Next in the generic setup, let's specify the document loader we want to use. You can download the `state_of_the_union.txt` file [here](https://github.com/hwchase17/langchain/blob/master/docs/modules/state_of_the_union.txt)"
    ]
   },
   {
@@ -366,7 +366,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.9.1"
+   "version": "3.10.9"
   },
   "vscode": {
    "interpreter": {