deps: update dependency org.springframework.boot:spring-boot to v3.4.2 (googleapis#1897)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [org.springframework.boot:spring-boot](https://spring.io/projects/spring-boot) ([source](https://redirect.github.com/spring-projects/spring-boot)) | `3.4.1` -> `3.4.2` | [![age](https://developer.mend.io/api/mc/badges/age/maven/org.springframework.boot:spring-boot/3.4.2?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/org.springframework.boot:spring-boot/3.4.2?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/org.springframework.boot:spring-boot/3.4.1/3.4.2?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/org.springframework.boot:spring-boot/3.4.1/3.4.2?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>spring-projects/spring-boot (org.springframework.boot:spring-boot)</summary>

### [`v3.4.2`](https://redirect.github.com/spring-projects/spring-boot/compare/v3.4.1...v3.4.2)

</details>

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Author: renovate-bot

samples/quickperf/pom.xml

@@ -79,7 +79,7 @@
     <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot</artifactId>
-      <version>3.4.1</version>
+      <version>3.4.2</version>
       <scope>test</scope>
     </dependency>
     <dependency>