Bump org.postgresql:postgresql in /retail/inventory-postgres-kafka

Bumps [org.postgresql:postgresql](https://github.com/pgjdbc/pgjdbc) from 42.4.1 to 42.4.4.
- [Release notes](https://github.com/pgjdbc/pgjdbc/releases)
- [Changelog](https://github.com/pgjdbc/pgjdbc/blob/master/CHANGELOG.md)
- [Commits](pgjdbc/pgjdbc@REL42.4.1...REL42.4.4)

---
updated-dependencies:
- dependency-name: org.postgresql:postgresql
  dependency-version: 42.4.4
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

retail/inventory-postgres-kafka/pom.xml

@@ -172,7 +172,7 @@
         <dependency>
             <groupId>org.postgresql</groupId>
             <artifactId>postgresql</artifactId>
-            <version>42.4.1</version>
+            <version>42.4.4</version>
         </dependency>
         <dependency>
             <groupId>org.apache.kafka</groupId>