Update impl/README.md

Co-authored-by: Ricardo Zanini <1538000+ricardozanini@users.noreply.github.com>

Author: fjtirado

impl/README.md

@@ -128,7 +128,9 @@ In order to execute the workflow without blocking the calling thread till the HT
 ```
 When the HTTP request is done, both examples will print a similar output
 
-`Workflow output is {"id":10,"category":{"id":10,"name":"string"},"name":"doggie","photoUrls":["string"],"tags":[{"id":10,"name":"string"}],"status":"string"}`
+
+```shell
+Workflow output is {"id":10,"category":{"id":10,"name":"string"},"name":"doggie","photoUrls":["string"],"tags":[{"id":10,"name":"string"}],"status":"string"}
 
 You can find the complete java code [here](../examples/simpleGet/src/main/java/NotBlockingExample.java)