Update spring boot to v3.4.0

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
org.springframework.boot:spring-boot (source)	3.3.5 -> 3.4.0
org.springframework.boot:spring-boot-starter-parent (source)	3.3.5 -> 3.4.0

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Release Notes

spring-projects/spring-boot (org.springframework.boot:spring-boot)

### [`v3.4.0`](https://redirect.github.com/spring-projects/spring-boot/compare/v3.3.6...v3.4.0) ### [`v3.3.6`](https://redirect.github.com/spring-projects/spring-boot/compare/v3.3.5...v3.3.6)

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