Bump postgresql from 42.3.3 to 42.3.4

Bumps [postgresql](https://github.com/pgjdbc/pgjdbc) from 42.3.3 to 42.3.4.
- [Release notes](https://github.com/pgjdbc/pgjdbc/releases)
- [Changelog](https://github.com/pgjdbc/pgjdbc/blob/master/CHANGELOG.md)
- [Commits](pgjdbc/pgjdbc@REL42.3.3...REL42.3.4)

---
updated-dependencies:
- dependency-name: org.postgresql:postgresql
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

crawler4j-examples/crawler4j-examples-postgres/pom.xml

@@ -10,7 +10,7 @@
     <modelVersion>4.0.0</modelVersion>
 
     <properties>
-        <postgresql.version>42.3.3</postgresql.version>
+        <postgresql.version>42.3.4</postgresql.version>
         <c3p0.version>0.9.5.5</c3p0.version>
         <flyway.db.version>8.5.4</flyway.db.version>
     </properties>