Upgrade PostgreSql JDBC driver to 42.4.0

Closes #1266

pom.xml

@@ -36,7 +36,7 @@
 		<mariadb-java-client.version>2.7.5</mariadb-java-client.version>
 		<mssql.version>9.2.1.jre8</mssql.version>
 		<mysql-connector-java.version>8.0.29</mysql-connector-java.version>
-		<postgresql.version>42.3.5</postgresql.version>
+		<postgresql.version>42.4.0</postgresql.version>
 		<oracle.version>19.6.0.0</oracle.version>
 
 		<!-- test utilities-->

spring-data-r2dbc/pom.xml

@@ -26,7 +26,7 @@
 		<sonar.dynamicAnalysis>reuseReports</sonar.dynamicAnalysis>
 
 		<degraph-check.version>0.1.4</degraph-check.version>
-		<postgresql.version>42.2.25</postgresql.version>
+		<postgresql.version>42.4.0</postgresql.version>
 		<mysql.version>8.0.29</mysql.version>
 		<r2dbc-spi-test.version>0.9.1.RELEASE</r2dbc-spi-test.version>
 		<mssql-jdbc.version>7.1.2.jre8-preview</mssql-jdbc.version>