Update spring boot to v3.4.3

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
org.springframework.boot (source)	3.4.2 -> 3.4.3
org.springframework.boot:spring-boot-dependencies (source)	3.4.2 -> 3.4.3

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Release Notes

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

v3.4.3

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Configuration

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