Update to Spring Data Redis 1.8.23.RELEASE

Fixes gh-7945

Author: rwinch

gradle/javaprojects.gradle

@@ -34,7 +34,7 @@ ext.slf4jVersion = '1.7.25'
 ext.spockVersion = '0.7-groovy-2.0'
 ext.springDataCommonsVersion = '1.13.23.RELEASE'
 ext.springDataJpaVersion = '1.11.23.RELEASE'
-ext.springDataRedisVersion = '1.8.20.RELEASE'
+ext.springDataRedisVersion = '1.8.23.RELEASE'
 ext.springSessionVersion = '1.3.4.RELEASE'
 ext.springBootVersion = '1.5.16.RELEASE'
 ext.thymeleafVersion = '3.0.9.RELEASE'