deps: bump spring-cloud-config.version from 4.1.3 to 4.2.0

Bumps `spring-cloud-config.version` from 4.1.3 to 4.2.0.

Updates `org.springframework.cloud:spring-cloud-starter-bootstrap` from 4.1.3 to 4.2.0
- [Release notes](https://github.com/spring-cloud/spring-cloud-commons/releases)
- [Commits](spring-cloud/spring-cloud-commons@v4.1.3...v4.2.0)

Updates `org.springframework.cloud:spring-cloud-config-dependencies` from 4.1.3 to 4.2.0
- [Release notes](https://github.com/spring-cloud/spring-cloud-build/releases)
- [Commits](spring-cloud/spring-cloud-build@v4.1.3...v4.2.0)

---
updated-dependencies:
- dependency-name: org.springframework.cloud:spring-cloud-starter-bootstrap
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.springframework.cloud:spring-cloud-config-dependencies
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

spring-cloud-gcp-samples/spring-cloud-gcp-pubsub-bus-config-sample/pom.xml

@@ -14,7 +14,7 @@
     <name>Spring Framework on Google Cloud Code Sample - Pub/Sub Bus Configuration Management</name>
 
     <properties>
-        <spring-cloud-config.version>4.1.3</spring-cloud-config.version>
+        <spring-cloud-config.version>4.2.0</spring-cloud-config.version>
     </properties>
 
     <!-- The Spring Framework on Google Cloud BOM will manage spring-cloud-gcp version numbers for you. -->