Bump org.apache.activemq:activemq-client in /modules/activemq

Bumps [org.apache.activemq:activemq-client](https://github.com/apache/activemq) from 6.2.0 to 6.2.4.
- [Release notes](https://github.com/apache/activemq/releases)
- [Commits](https://github.com/apache/activemq/compare/activemq-6.2.0...activemq-6.2.4)

---
updated-dependencies:
- dependency-name: org.apache.activemq:activemq-client
  dependency-version: 6.2.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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