Upgrade postgresql jdbc version to latest.

Author: umartin

PgBulkInsert/pom.xml

@@ -130,7 +130,7 @@
         <maven.compiler.target>1.8</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 
-        <postgresql.version>42.2.19</postgresql.version>
+        <postgresql.version>42.6.0</postgresql.version>
         <junit.version>4.13.1</junit.version>
     </properties>