Upgrade to Hibernate Validator 6.0.20.Final

Closes gh-21810

Author: snicoll

spring-boot-project/spring-boot-dependencies/pom.xml

@@ -72,7 +72,7 @@
 		<hazelcast.version>3.11.7</hazelcast.version>
 		<hazelcast-hibernate5.version>1.2.3</hazelcast-hibernate5.version>
 		<hibernate.version>5.3.17.Final</hibernate.version>
-		<hibernate-validator.version>6.0.19.Final</hibernate-validator.version>
+		<hibernate-validator.version>6.0.20.Final</hibernate-validator.version>
 		<hikaricp.version>3.2.0</hikaricp.version>
 		<hsqldb.version>2.4.1</hsqldb.version>
 		<htmlunit.version>2.33</htmlunit.version>