Update 'README.md'

README.md

@@ -12,10 +12,9 @@ This guide walks you through the process of creating a "hello world" link:/under
 
 You'll build a service that will accept HTTP GET requests at:
 
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+```
 http://localhost:8080/greeting
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-
+```
 and respond with a link:/understanding/JSON[JSON] representation of a greeting:
 
 [source,json]