mark ttrpc-example as non-publishable

add publish = false to ttrpc-example to avoid publishing it by mistake

Signed-off-by: Jorge Prendes <jorge.prendes@gmail.com>

Author: jprendes

example/Cargo.toml

@@ -9,6 +9,7 @@ readme = "README.md"
 repository = "https://github.com/alipay/ttrpc-rust"
 homepage = "https://github.com/alipay/ttrpc-rust"
 description = "An example of ttrpc."
+publish = false
 
 [dev-dependencies]
 protobuf = "3.7.2"