Fix checkstyle violation in OAuth sample

Author: philwebb

spring-boot-samples/spring-boot-sample-oauth2-client/src/main/resources/application.yml

@@ -16,4 +16,4 @@ spring:
             client-name: Github email
             provider: github
             scope: user:email
-            redirect-uri-template: http://localhost:8080/login/oauth2/code/github
+            redirect-uri-template: http://localhost:8080/login/oauth2/code/github