Update to Thymeleaf 3.0.8.RELEASE

Issue: gh-4608

gradle/dependency-management.gradle

@@ -203,8 +203,7 @@ dependencyManagement {
 		dependency 'org.slf4j:slf4j-nop:1.7.12'
 		dependency 'org.sonatype.sisu.inject:cglib:2.2.1-v20090111'
 		dependency 'org.springframework.ldap:spring-ldap-core:2.3.1.RELEASE'
-		dependency 'org.thymeleaf:thymeleaf-spring5:3.0.6.M4'
-		dependency 'org.thymeleaf:thymeleaf:3.0.6.RELEASE'
+		dependency 'org.thymeleaf:thymeleaf-spring5:3.0.8.RELEASE'
 		dependency 'org.unbescape:unbescape:1.1.4.RELEASE'
 		dependency 'org.w3c.css:sac:1.3'
 		dependency 'xalan:serializer:2.7.2'