Bump spring.boot.version from 3.5.5 to 3.5.6 (SolaceProducts#417)

Bumps `spring.boot.version` from 3.5.5 to 3.5.6.

Updates `org.springframework.boot:spring-boot-maven-plugin` from 3.5.5 to 3.5.6
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v3.5.5...v3.5.6)

Updates `org.springframework.boot:spring-boot-dependencies` from 3.5.5 to 3.5.6
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v3.5.5...v3.5.6)

---
updated-dependencies:
- dependency-name: org.springframework.boot:spring-boot-maven-plugin
  dependency-version: 3.5.6
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: org.springframework.boot:spring-boot-dependencies
  dependency-version: 3.5.6
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

pom.xml

@@ -30,7 +30,7 @@
 
         <!-- Override spring-boot version from solace-spring-boot to latest patch version -->
         <!-- Remove this if the next version of solace-spring-boot works fine -->
-        <spring.boot.version>3.5.5</spring.boot.version>
+        <spring.boot.version>3.5.6</spring.boot.version>
 
         <solace.spring.cloud.stream-starter.version>5.10.1-SNAPSHOT</solace.spring.cloud.stream-starter.version>