Bump grpc-spring-boot-starter from 4.0.0 to 4.2.1 (#1766)
Bump grpc-spring-boot-starter from 4.0.0 to 4.2.1 (#1766)

Bumps [grpc-spring-boot-starter](https://github.com/LogNet/grpc-spring-boot-starter) from 4.0.0 to 4.2.1.
- [Release notes](https://github.com/LogNet/grpc-spring-boot-starter/releases)
- [Changelog](https://github.com/LogNet/grpc-spring-boot-starter/blob/master/ReleaseNotes.adoc)
- [Commits](https://github.com/LogNet/grpc-spring-boot-starter/compare/v.4.0.0...v.4.2.1)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>

Co-authored-by: dependabot-preview[bot] <6a4c1c4838f800d1998274cd5234e1f65c55e90c@users.noreply.github.com>
spring-cloud/spring-cloud-sleuth,spring-cloud/spring-cloud-sleuth,spring-cloud/spring-cloud-sleuth,spring-cloud/spring-cloud-sleuth,spring-cloud/spring-cloud-sleuth