Bump org.postgresql:postgresql

Bumps [org.postgresql:postgresql](https://github.com/pgjdbc/pgjdbc) from 42.1.0 to 42.3.9.
- [Release notes](https://github.com/pgjdbc/pgjdbc/releases)
- [Changelog](https://github.com/pgjdbc/pgjdbc/blob/master/CHANGELOG.md)
- [Commits](pgjdbc/pgjdbc@REL42.1.0...REL42.3.9)

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

Signed-off-by: dependabot[bot] <support@github.com>

test-data/maven/multi-module-multi-branch/bs-libraries/pom.xml

@@ -21,7 +21,7 @@
         <dependency>
           <groupId>org.postgresql</groupId>
           <artifactId>postgresql</artifactId>
-          <version>42.5.0</version>
+          <version>42.3.9</version>
         </dependency>
       </dependencies>
     </dependencyManagement>

test-data/maven/multi-module-multi-branch/pom.xml

@@ -68,7 +68,7 @@
             <dependency>
               <groupId>org.postgresql</groupId>
               <artifactId>postgresql</artifactId>
-              <version>42.1.0</version>
+              <version>42.3.9</version>
             </dependency>
         </dependencies>
     </dependencyManagement>