docs(maps-places): add link to client library examples (#11597)

b/421118724

Author: meltsufin

java-maps-places/.readme-partials.yaml

@@ -0,0 +1,4 @@
+custom_content: |
+  ### Client Library Usage Examples
+
+  [Client library examples](https://developers.google.com/maps/documentation/places/web-service/client-library-examples#java) of how to use the Places API (New) are available to help you get started.