deps: bump gapic-generator-java-bom.version from 2.23.1 to 2.24.0 (#2097

)

Bumps `gapic-generator-java-bom.version` from 2.23.1 to 2.24.0.

Updates `com.google.api:gapic-generator-java-bom` from 2.23.1 to 2.24.0
- [Release notes](https://github.com/googleapis/sdk-platform-java/releases)
- [Changelog](https://github.com/googleapis/sdk-platform-java/blob/main/CHANGELOG.md)
- [Commits](googleapis/sdk-platform-java@v2.23.1...v2.24.0)

Updates `com.google.api:gapic-generator-java:testlib` from 2.23.1 to 2.24.0
- [Release notes](https://github.com/googleapis/sdk-platform-java/releases)
- [Changelog](https://github.com/googleapis/sdk-platform-java/blob/main/CHANGELOG.md)
- [Commits](googleapis/sdk-platform-java@v2.23.1...v2.24.0)

---
updated-dependencies:
- dependency-name: com.google.api:gapic-generator-java-bom
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: com.google.api:gapic-generator-java:testlib
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

spring-cloud-generator/pom.xml

@@ -15,7 +15,7 @@
     <description>Spring Code Generator for Google Cloud</description>
 
     <properties>
-        <gapic-generator-java-bom.version>2.23.1</gapic-generator-java-bom.version>
+        <gapic-generator-java-bom.version>2.24.0</gapic-generator-java-bom.version>
         <!-- [gapic-test]: protobuf.version for compiling protos used in unit testing
              this should be consistent with version in gapic-generator-java-bom -->
         <protobuf.version>3.23.2</protobuf.version>