docs(vertex.md): add vertex ai grounding to docs

docs/my-website/docs/providers/vertex.md

@@ -330,6 +330,51 @@ Return a `list[Recipe]`
 completion(model="vertex_ai_beta/gemini-1.5-flash-preview-0514", messages=messages, response_format={ "type": "json_object" })
 ```
 
+### **Grounding**
+
+Add Google Search Result grounding to vertex ai calls. 
+
+<Tabs>
+<TabItem value="sdk" label="SDK">
+
+```python 
+from litellm import completion 
+
+## SETUP ENVIRONMENT
+# !gcloud auth application-default login - run this to add vertex credentials to your env
+
+tools = [{"googleSearchRetrieval": {}}] # 👈 ADD GOOGLE SEARCH
+
+resp = litellm.completion(
+                    model="vertex_ai_beta/gemini-1.0-pro-001",
+                    messages=[{"role": "user", "content": "Who won the world cup?"}],
+                    tools=tools,
+                )
+
+print(resp)
+```
+</TabItem>
+<TabItem value="proxy" label="PROXY">
+
+```bash
+curl http://0.0.0.0:4000/v1/chat/completions \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer $OPENAI_API_KEY" \
+  -d '{
+    "model": "gpt-4o",
+    "messages": [{"role": "user", "content": "Who won the world cup?"}],
+    "tools": [
+        {
+            "googleSearchResults": {} 
+        }
+    ]
+  }'
+
+```
+
+</TabItem>
+</Tabs>
+
 ## Pre-requisites
 * `pip install google-cloud-aiplatform` (pre-installed on proxy docker image)
 * Authentication: