Upgrade to HikariCP-java6 2.3.13

Closes gh-5215

Author: wilkinsona

spring-boot-dependencies/pom.xml

@@ -79,7 +79,7 @@
 		<hibernate.version>4.3.11.Final</hibernate.version>
 		<hibernate-validator.version>5.2.2.Final</hibernate-validator.version>
 		<hikaricp.version>2.4.3</hikaricp.version>
-		<hikaricp-java6.version>2.3.12</hikaricp-java6.version>
+		<hikaricp-java6.version>2.3.13</hikaricp-java6.version>
 		<hornetq.version>2.4.7.Final</hornetq.version>
 		<hsqldb.version>2.3.3</hsqldb.version>
 		<httpasyncclient.version>4.1.1</httpasyncclient.version>