fix(kotlin-spring): add trailing newline to clientConfiguration template

Author: yonatankarp

modules/openapi-generator/src/main/resources/kotlin-spring/libraries/spring-cloud/clientConfiguration.mustache

@@ -208,4 +208,4 @@ class ClientConfiguration {
     }
     {{/hasOAuthMethods}}
 {{/useSpringBoot4}}
-}
+}