add to gallery (#824)

Author: hwchase17

docs/gallery.rst

@@ -77,6 +77,17 @@ Open Source
 
     +++
 
+    A jupyter notebook demonstrating how you could create a semantic search engine on documents in one of your Google Folders
+
+    ---
+
+    .. link-button:: https://github.com/venuv/langchain_semantic_search
+        :type: url
+        :text: Google Folder Semantic Search
+        :classes: stretched-link btn-lg
+
+    +++
+
     Build a GitHub support bot with GPT3, LangChain, and Python.
 
     ---