build(deps): bump certifi in /examples/confluent-example (#203)

Bumps [certifi](https://github.com/certifi/python-certifi) from 2024.6.2 to 2024.7.4.
- [Commits](certifi/python-certifi@2024.06.02...2024.07.04)

---
updated-dependencies:
- dependency-name: certifi
  dependency-type: indirect
...

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