Bump tecnickcom/tcpdf from 6.7.2 to 6.7.4 in /src

Bumps [tecnickcom/tcpdf](https://github.com/tecnickcom/TCPDF) from 6.7.2 to 6.7.4.
- [Changelog](https://github.com/tecnickcom/TCPDF/blob/main/CHANGELOG.TXT)
- [Commits](https://github.com/tecnickcom/TCPDF/commits/6.7.4)

---
updated-dependencies:
- dependency-name: tecnickcom/tcpdf
  dependency-type: direct:production
...

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