Edit example.rst (#3660)

Removed duplicate 'public' word on the GET /app/log/public/ endpoint description (C++ logging application example)

doc/build_apps/example.rst

@@ -41,7 +41,7 @@ The Logging application implements a trivial protocol, made up of four transacti
             "msg": "A sample public log message"
         }
 
-- :http:GET:`/app/log/public`, which retrieves a public public log from a given index written by a previous :http:POST:`/app/log/public` call.
+- :http:GET:`/app/log/public`, which retrieves a public log from a given index written by a previous :http:POST:`/app/log/public` call.
 
     Get a public message:
 
@@ -58,4 +58,4 @@ The C++ implementation of the Logging application is located in the :ccf_repo:`s
 
    logging_cpp
    logging_rpc_api
-   logging
+   logging