OAK-8481: RDB*Store: update postgresql jdbc driver reference to 42.4.6

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1863076 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/oak-parent/pom.xml b/oak-parent/pom.xml
index eba67ee..3af7614 100644
--- a/oak-parent/pom.xml
+++ b/oak-parent/pom.xml
@@ -1061,7 +1061,7 @@
         <dependency>
           <groupId>org.postgresql</groupId>
           <artifactId>postgresql</artifactId>
-          <version>42.2.5</version>
+          <version>42.2.6</version>
         </dependency>
       </dependencies>
     </profile>