docs(docs): add link for ALPHAVANTAGE_API_KEY generation in integration notebook (#32364)

docs(alpha_vantage): add link for ALPHAVANTAGE_API_KEY generation in
integration notebook

**Description:**

This PR updates the `docs/docs/integrations/tools/alpha_vantage.ipynb`
integration notebook to help users locate the API key registration page
for Alpha Vantage. The following markdown line was added:

---------

Co-authored-by: Mason Daugherty <[email protected]>

Author: dhanesh24g

docs/docs/integrations/tools/alpha_vantage.ipynb

@@ -9,7 +9,9 @@
    "source": [
     "# Alpha Vantage\n",
     "\n",
-    ">[Alpha Vantage](https://www.alphavantage.co) Alpha Vantage provides realtime and historical financial market data through a set of powerful and developer-friendly data APIs and spreadsheets. \n",
+    ">[Alpha Vantage](https://www.alphavantage.co) Alpha Vantage provides realtime and historical financial market data through a set of powerful and developer-friendly data APIs and spreadsheets.\n",
+    "\n",
+    "Generate the `ALPHAVANTAGE_API_KEY` [at their website](https://www.alphavantage.co/support/#api-key)\n.",
     "\n",
     "Use the ``AlphaVantageAPIWrapper`` to get currency exchange rates."
    ]