PiT 24.3: Demo projects should be updated to latest stable version

[manolo]

Describe the bug

This projects should be bump to latest version

• initializer-hilla-maven 2.1.9 -> 2.4.0
  • [x] https://github.com/spring-io/start.spring.io/pull/1363
• TatuLund/mpr-demo:mpr-7 24.1.4 -> 24.2.5
  • [x] https://github.com/TatuLund/mpr-demo/pull/8
• spring-guides/gs-crud-with-vaadin/complete 24.1.5 -> 24.2.5
  • [ ] https://github.com/spring-guides/gs-crud-with-vaadin/pull/111
• spring-petclinic/spring-petclinic-vaadin-flow 24.1.6 -> 24.2.5
  • [x] https://github.com/spring-petclinic/spring-petclinic-vaadin-flow/pull/6