Upgrade to Selenium 2.53.1

Closes gh-6478

spring-boot-dependencies/pom.xml

@@ -134,7 +134,7 @@
 		<postgresql.version>9.4.1209.jre7</postgresql.version>
 		<reactor.version>2.0.8.RELEASE</reactor.version>
 		<reactor-spring.version>2.0.7.RELEASE</reactor-spring.version>
-		<selenium.version>2.53.0</selenium.version>
+		<selenium.version>2.53.1</selenium.version>
 		<sendgrid.version>2.2.2</sendgrid.version>
 		<servlet-api.version>3.1.0</servlet-api.version>
 		<simple-json.version>1.1.1</simple-json.version>