Bump org.postgresql:postgresql in /kstreams-live-update/event-source

Bumps [org.postgresql:postgresql](https://github.com/pgjdbc/pgjdbc) from 42.5.1 to 42.7.2.
- [Release notes](https://github.com/pgjdbc/pgjdbc/releases)
- [Changelog](https://github.com/pgjdbc/pgjdbc/blob/master/CHANGELOG.md)
- [Commits](https://github.com/pgjdbc/pgjdbc/commits)

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

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

kstreams-live-update/event-source/pom.xml

@@ -32,7 +32,7 @@
         <dependency>
             <groupId>org.postgresql</groupId>
             <artifactId>postgresql</artifactId>
-            <version>42.5.1</version>
+            <version>42.7.2</version>
         </dependency>
         <dependency>
             <groupId>org.slf4j</groupId>