Bump postgresql from 42.2.18 to 42.4.1 in /oak-parent

Bumps [postgresql](https://github.com/pgjdbc/pgjdbc) from 42.2.18 to 42.4.1.
- [Release notes](https://github.com/pgjdbc/pgjdbc/releases)
- [Changelog](https://github.com/pgjdbc/pgjdbc/blob/master/CHANGELOG.md)
- [Commits](https://github.com/pgjdbc/pgjdbc/compare/REL42.2.18...REL42.4.1)

---
updated-dependencies:
- dependency-name: org.postgresql:postgresql
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/oak-parent/pom.xml b/oak-parent/pom.xml
index 3ef7bb9..7d6f492 100644
--- a/oak-parent/pom.xml
+++ b/oak-parent/pom.xml
@@ -1127,7 +1127,7 @@
         <dependency>
           <groupId>org.postgresql</groupId>
           <artifactId>postgresql</artifactId>
-          <version>42.2.18</version>
+          <version>42.4.1</version>
         </dependency>
       </dependencies>
     </profile>